Category: Operating System Objective Questions

Operating System Multiple Choice Questions on “Protection – Access Matrix”.

1. In domain structure what is Access-right equal to?
a) Access-right = object-name, rights-set
b) Access-right = read-name, write-set
c) Access-right = read-name, execute-set
d) Access-right = object-name, execute-set

Answer: a

2. What is meaning of right-set?
a) It is a subset consist of read and write
b) It is a subset of all valid operations that can be performed on the object
c) It is a subset consist of read, write and execute
d) None of the mentioned

Answer: b

3. What is Domain?
a) Domain = Set of all objects
b) It is a collection of protection policies
c) Domain= set of access-rights
d) None of the mentioned

Answer: c

4. What does the access matrix represent?
a) Rows-Domains, Columns-Objects
b) Rows-Objects, Columns-Domains
c) Rows-Access List, Columns-Domains
d) Rows-Domains, Columns-Access list

Answer: a
Clarification: None.

5. What are the three additional operations to change the contents of the access-matrix?
a) copy
b) Owner
c) control
d) all of the mentioned

Answer: d
Clarification: None.

6. Who can add new rights and remove some rights?
a) copy
b) transfer
c) limited copy
d) owner

Answer: d
Clarification: None.

7. What are the three copyrights?
a) copy
b) transfer
c) limited copy
d) all of the mentioned

Answer: d
Clarification: None.

8. Which two rights allow a process to change the entries in a column?
a) copy and transfer
b) copy and owner
c) owner and transfer
d) deny and copy

Answer: a
Clarification: None.

9. Which is an unsolvable problem in access-matrix?
a) Owner override
b) Brute force
c) Access denied
d) Confinement

Answer: d
Clarification: None.

10. Which of the following objects require protection?
a) CPU
b) Printers
c) Motherboard
d) All of the mentioned

Answer: b
Clarification: None.

11. What is ‘separation’ in security of Operating systems?
a) To have separate login for different users
b) To have separate Hard disk drive/partition for different users
c) It means keeping one user’s objects separate from other users
d) None of the mentioned

Answer: c
Clarification: None.

12. Which of the following statements are correct?
i) Physical separation – in which process use different physical objects like separate printers
ii) Physical separation – in which process having different security requirement at different times
iii) Logical separation – In which users operate under illusion that no other processes exist
iv) Logical separation – In which processes conceal their data and computations
a) i
b) i and iii
c) ii and iii
d) iii and iv

Answer: b
Clarification: None.

13. Which of the following statements are correct?
i) Physical separation – in which process use different physical objects like separate printers
ii) Temporal separation – in which process having different security requirement at different times
iii) Physical separation – In which users operate under illusion that no other processes exist
iv) Temporal separation – In which processes conceal their data and computations
a) i
b) i and ii
c) ii and iii
d) iii and iv

Answer: b
Clarification: None.

14. Which of the following statements are correct?
i) logical separation – in which process use different physical objects like separate printers
ii) cryptographic separation – in which process having different security requirement at different times
iii) Logical separation – In which users operate under illusion that no other processes exist
iv) cryptographic separation – In which processes conceal their data and computations
a) i
b) i and ii
c) ii and iii
d) iii and iv
View Answer

Answer: d
Clarification: None.

15. What are the various roles of protection?
a) It is used to detect errors which can prevent contamination of system
b) It is used used to accelerate a process
c) It is used to optimize system downtime
d) None of the mentioned

Answer: a
Clarification: None.

16. Which of the following objects require protection?
a) Memory
b) Monitor
c) Power supply unit
d) All of the mentioned

Answer: a

Operating System Multiple Choice Questions on “CPU Scheduling Benefits”.

1. CPU scheduling is the basis of ___________
a) multiprocessor systems
b) multiprogramming operating systems
c) larger memory sized systems
d) none of the mentioned

Answer: b
Clarification: None.

2. With multiprogramming ______ is used productively.
a) time
b) space
c) money
d) all of the mentioned

Answer: a
Clarification: None.

3. What are the two steps of a process execution?
a) I/O & OS Burst
b) CPU & I/O Burst
c) Memory & I/O Burst
d) OS & Memory Burst

Answer: b
Clarification: None.

4. An I/O bound program will typically have ____________
a) a few very short CPU bursts
b) many very short I/O bursts
c) many very short CPU bursts
d) a few very short I/O bursts

Answer: c
Clarification: None.

5. A process is selected from the ______ queue by the ________ scheduler, to be executed.
a) blocked, short term
b) wait, long term
c) ready, short term
d) ready, long term

Answer: c
Clarification: None.

6. In the following cases non – preemptive scheduling occurs?
a) When a process switches from the running state to the ready state
b) When a process goes from the running state to the waiting state
c) When a process switches from the waiting state to the ready state
d) All of the mentioned

Answer: b
Clarification: There is no other choice.

7. The switching of the CPU from one process or thread to another is called ____________
a) process switch
b) task switch
c) context switch
d) all of the mentioned

Answer: d
Clarification: None.

8. What is Dispatch latency?
a) the speed of dispatching a process from running to the ready state
b) the time of dispatching a process from running to ready state and keeping the CPU idle
c) the time to stop one process and start running another one
d) none of the mentioned

Answer: c
Clarification: None.

9. Scheduling is done so as to ____________
a) increase CPU utilization
b) decrease CPU utilization
c) keep the CPU more idle
d) none of the mentioned

Answer: a
Clarification: None.

10. Scheduling is done so as to ____________
a) increase the throughput
b) decrease the throughput
c) increase the duration of a specific amount of work
d) none of the mentioned

Answer: a
Clarification: None.

11. What is Turnaround time?
a) the total waiting time for a process to finish execution
b) the total time spent in the ready queue
c) the total time spent in the running queue
d) the total time from the completion till the submission of a process

Answer: d
Clarification: None.

12. Scheduling is done so as to ____________
a) increase the turnaround time
b) decrease the turnaround time
c) keep the turnaround time same
d) there is no relation between scheduling and turnaround time

Answer: b
Clarification: None.

13. What is Waiting time?
a) the total time in the blocked and waiting queues
b) the total time spent in the ready queue
c) the total time spent in the running queue
d) the total time from the completion till the submission of a process

Answer: b
Clarification: None.

14. Scheduling is done so as to ____________
a) increase the waiting time
b) keep the waiting time the same
c) decrease the waiting time
d) none of the mentioned

Answer: c
Clarification: None.

15. What is Response time?
a) the total time taken from the submission time till the completion time
b) the total time taken from the submission time till the first response is produced
c) the total time taken from submission time till the response is output
d) none of the mentioned

Answer: b

Operating System Multiple Choice Questions on “Memory Management”.

1. CPU fetches the instruction from memory according to the value of ____________
a) program counter
b) status register
c) instruction register
d) program status word

Answer: a
Clarification: None.

2. A memory buffer used to accommodate a speed differential is called ____________
a) stack pointer
b) cache
c) accumulator
d) disk buffer

Answer: b
Clarification: None.

3. Which one of the following is the address generated by CPU?
a) physical address
b) absolute address
c) logical address
d) none of the mentioned

Answer: c
Clarification: None.

4. Run time mapping from virtual to physical address is done by ____________
a) Memory management unit
b) CPU
c) PCI
d) None of the mentioned

Answer: a
Clarification: None.

5. Memory management technique in which system stores and retrieves data from secondary storage for use in main memory is called?
a) fragmentation
b) paging
c) mapping
d) none of the mentioned

Answer: b
Clarification: None.

6. The address of a page table in memory is pointed by ____________
a) stack pointer
b) page table base register
c) page register
d) program counter

Answer: b
Clarification: None.

7. Program always deals with ____________
a) logical address
b) absolute address
c) physical address
d) relative address

Answer: a
Clarification: None.

8. The page table contains ____________
a) base address of each page in physical memory
b) page offset
c) page size
d) none of the mentioned

Answer: a
Clarification: None.

9. What is compaction?
a) a technique for overcoming internal fragmentation
b) a paging technique
c) a technique for overcoming external fragmentation
d) a technique for overcoming fatal error

Answer: c
Clarification: None.

10. Operating System maintains the page table for ____________
a) each process
b) each thread
c) each instruction
d) each address

Answer: a

Operating System Questions and Answers on “Multimedia System – Compression” and will also be useful for GRE examinations.

1. The ability to move around within a media stream is known as ___________
a) buffering
b) random access
c) access
d) sequential access

Answer: b
Clarification: None.

2. What are the two types of real time streaming?
a) live & on demand streaming
b) dead & static streaming
c) static & on demand streaming
d) on demand streaming

Answer: a
Clarification: None.

3. Random access is not allowed in ___________
a) live streaming
b) dead streaming
c) static streaming
d) on demand streaming

Answer: a
Clarification: None.

4. The streaming that takes place as the event is occurring is ___________
a) live streaming
b) dead streaming
c) static streaming
d) on demand streaming

Answer: d
Clarification: None.

5. For a computer to deliver continuous media it must guarantee the specific rate and timing requirements, also known as ___________
a) deadline
b) quality of service
c) period
d) burst time

Answer: b
Clarification: None.

6. For QOS to be implemented properly ___________
a) file systems must be efficient to meet the rate requirements of continuous media
b) network protocols must support bandwidth requirements while minimizing delay and jitter
c) all of the mentioned
d) none of the mentioned

Answer: c
Clarification: None.

7. What will happen once a file is compressed?
a) it has a better quality
b) it takes up less space for storage
c) it cannot be delivered to the client more quickly
d) none of the mentioned

Answer: b
Clarification: None.

8. Compression ratio is the ratio of ___________
a) the original file size to the size of the compressed file
b) the number of pixels in a frame of the original size to those in a frame of the compressed file
c) compressed file size to the original file size
d) none of the mentioned

Answer: a
Clarification: None.

9. Lossy and lossless are classifications of ___________
a) multimedia storage systems
b) files
c) compression algorithms
d) all of the mentioned

Answer: c
Clarification: None.

10. Lossy techniques provide ___________ when compared to lossless techniques.
a) lower compression ratios
b) much higher compression ratios
c) similar compression ratios
d) none of the mentioned

Answer: b

Operating System Multiple Choice Questions on “Signal Handling”.

1. Signals that occur at the same time, are presented to the process ____________
a) one at a time, in a particular order
b) one at a time, in no particular order
c) all at a time
d) none of the mentioned

Answer: b

2. Which of the following is not TRUE?
a) Processes may send each other signals
b) Kernel may send signals internally
c) A field is updated in the signal table when the signal is sent
d) Each signal is maintained by a single bit

Answer: c
Clarification: A field is updated in the process table when the signal is sent.

3. Signals of a given type ____________
a) are queued
b) are all sent as one
c) cannot be queued
d) none of the mentioned

Answer: b
Clarification: The signal handler will be invoked only once.

4. The three ways in which a process responds to a signal are ____________
a) ignoring the signal
b) handling the signal
c) performing some default action
d) all of the mentioned

Answer: d
Clarification: None.

5. Signals are identified by ____________
a) signal identifiers
b) signal handlers
c) signal actions
d) none of the mentioned

Answer: a
Clarification: None.

6. When a process blocks the receipt of certain signals?
a) The signals are delivered
b) The signals are not delivered
c) The signals are received until they are unblocked
d) The signals are received by the process once they are delivered

Answer: a
Clarification: None.

7. The _______ maintains pending and blocked bit vectors in the context of each process.
a) CPU
b) Memory
c) Process
d) Kernel

Answer: d
Clarification: None.

8. In UNIX, the set of masked signals can be set or cleared using the ________ function.
a) sigmask
b) sigmaskproc
c) sigprocmask
d) sigproc

Answer: c
Clarification: None.

9. The usefulness of signals as a general inter process communication mechanism is limited because ____________
a) they do not work between processes
b) they are user generated
c) they cannot carry information directly
d) none of the mentioned

Answer: c
Clarification: None.

10. The usual effect of abnormal termination of a program is ____________
a) core dump file generation
b) system crash
c) program switch
d) signal destruction

Answer: a
Clarification: None.

11. In UNIX, the abort() function sends the ________ signal to the calling process, causing abnormal termination.
a) SIGTERM
b) SIGSTOP
c) SIGABORT
d) SIGABRT

Answer: d
Clarification: None.

12. In most cases, if a process is sent a signal while it is executing a system call ____________
a) the system call will continue execution and the signal will be ignored completely
b) the system call is interrupted by the signal, and the signal handler comes in
c) the signal has no effect until the system call completes
d) none of the mentioned

Answer: c
Clarification: None.

13. A process can never be sure that a signal it has sent _____________
a) has which identifier
b) has not been lost
c) has been sent
d) all of the mentioned

Answer: b
Clarification: None.

14. In UNIX, the ______________ system call is used to send a signal.
a) sig
b) send
c) kill
d) sigsend

Answer: c