Vaidikalaya

MCQ On OS Process

Q1. The systems which allow only one process execution at a time, are called __________.
  1. uniprogramming systems
  2. uniprocessing systems
  3. unitasking systems
  4. none of the mentioned

Answer: b, uniprocessing systems

Solution: Those systems which allow more than one process execution at a time are multiprocessing systems. Uniprocessing means only one processor.

Q2. In operating system, each process has its own __________.
  1. address space and global variables
  2. open files
  3. pending alarms, signals and signal handlers
  4. all of the mentioned

Answer: d, all of the mentioned

Solution: Each process has its own address space (code, data, stack, heap), open files, pending alarms, signals, and handlers.

Q3. A process can be terminated due to __________.
  1. normal exit
  2. fatal error
  3. killed by another process
  4. all of the mentioned

Answer: d, all of the mentioned

Solution: Processes can terminate normally, due to fatal error, or be killed by another process.

Q4. What is the ready state of a process?.
  1. when process is scheduled to run after some execution
  2. when process is unable to run until some task has been completed
  3. when process is using the CPU
  4. none of the mentioned

Answer: a, when process is scheduled to run after some execution

Solution: Ready state means the process has all resources needed and is waiting for CPU allocation.

Q5. What is interprocess communication?.
  1. communication within the process
  2. communication between two process
  3. communication between two threads of same process
  4. none of the mentioned

Answer: b, communication between two process

Solution: IPC allows processes to communicate and synchronize without sharing the same address space.

Q6. A set of processes is deadlock if __________.
  1. each process is blocked and will remain so forever
  2. each process is terminated
  3. all processes are trying to kill each other
  4. none of the mentioned

Answer: a, each process is blocked and will remain so forever

Solution: Deadlock occurs when each process is blocked, waiting for a resource held by another.

Q7. A process stack does not contain __________.
  1. Function parameters
  2. Local variables
  3. Return addresses
  4. PID of child process

Answer: d, PID of child process

Solution: Process stack contains parameters, local variables, return addresses, but not child PID.

Q8. Which system call can be used by a parent process to determine the termination of child process?.
  1. wait
  2. exit
  3. fork
  4. get

Answer: a, wait

Solution: wait() is used by the parent to determine termination and collect child’s exit status.

Q9. A Process Control Block(PCB) does not contain which of the following?.
  1. Code
  2. Stack
  3. Bootstrap program
  4. Data

Answer: c, Bootstrap program

Solution: PCB contains code, stack, data but not bootstrap program.

Q10. The number of processes completed per unit time is known as __________.
  1. Output
  2. Throughput
  3. Efficiency
  4. Capacity

Answer: b, Throughput

Solution: Throughput = number of processes completed per unit time.

Q11. The state of a process is defined by __________.
  1. the final activity of the process
  2. the activity just executed by the process
  3. the activity to next be executed by the process
  4. the current activity of the process

Answer: d, the current activity of the process

Solution: Process state is defined by the current activity of the process.

Q12. Which of the following is not the state of a process?.
  1. New
  2. Old
  3. Waiting
  4. Running

Answer: b, Old

Solution: There is no state called 'Old'. Valid states are New, Ready, Running, Waiting, Terminated.

Q13. What is a Process Control Block?.
  1. Process type variable
  2. Data Structure
  3. A secondary storage section
  4. A Block in memory

Answer: b, Data Structure

Solution: PCB is a data structure containing process state, program counter, CPU registers, etc.

Q14. The entry of all the PCBs of the current processes is in __________.
  1. Process Register
  2. Program Counter
  3. Process Table
  4. Process Unit

Answer: c, Process Table

Solution: All PCBs of current processes are stored in the Process Table.

Q15. What is the degree of multiprogramming?.
  1. the number of processes executed per unit time
  2. the number of processes in the ready queue
  3. the number of processes in the I/O queue
  4. the number of processes in memory

Answer: d, the number of processes in memory

Solution: Degree of multiprogramming = number of processes in memory.

Q16. A single thread of control allows the process to perform __________.
  1. only one task at a time
  2. multiple tasks at a time
  3. only two tasks at a time
  4. all of the mentioned

Answer: a, only one task at a time

Solution: A single thread can perform only one task at a time.

Q17. What is the objective of multiprogramming?.
  1. Have a process running at all time
  2. Have multiple programs waiting in a queue ready to run
  3. To increase CPU utilization
  4. None of the mentioned

Answer: c, To increase CPU utilization

Solution: Objective: maximize CPU utilization by keeping processes ready.

Q18. The child process completes execution, but the parent keeps executing, then the child process is known as __________.
  1. Orphan
  2. Zombie
  3. Body
  4. Dead

Answer: b, Zombie

Solution: A terminated child whose parent still runs is a Zombie.

Q19. The child process can __________.
  1. be a duplicate of the parent process
  2. never be a duplicate of the parent process
  3. cannot have another program loaded into it
  4. never have another program loaded into it

Answer: a, be a duplicate of the parent process

Solution: Child process may be a duplicate of parent.

Q20. Which of the following do not belong to queues for processes?.
  1. Job Queue
  2. PCB queue
  3. Device Queue
  4. Ready Queue

Answer: b, PCB queue

Solution: Queues: Job, Ready, Device exist. PCB queue does not.

Q21. When the process issues an I/O request __________.
  1. It is placed in an I/O queue
  2. It is placed in a waiting queue
  3. It is placed in the ready queue
  4. It is placed in the Job queue

Answer: a, It is placed in an I/O queue

Solution: I/O requests place process into I/O queue.

Q22. What will happen when a process terminates?.
  1. It is removed from all queues
  2. It is removed from all, but the job queue
  3. Its process control block is de-allocated
  4. Its process control block is never de-allocated

Answer: a, It is removed from all queues

Solution: On termination, process is removed from all queues.

Q23. What is a long-term scheduler?.
  1. It selects processes which have to be brought into the ready queue
  2. It selects processes which have to be executed next and allocates CPU
  3. It selects processes which heave to remove from memory by swapping
  4. None of the mentioned

Answer: a, It selects processes which have to be brought into the ready queue

Solution: Long-term scheduler selects jobs into the ready queue.

Q24. What is a medium-term scheduler?.
  1. It selects which process has to be brought into the ready queue
  2. It selects which process has to be executed next and allocates CPU
  3. It selects which process to remove from memory by swapping
  4. None of the mentioned

Answer: c, It selects which process to remove from memory by swapping

Solution: Medium-term scheduler swaps processes in/out of memory.

Q25. What is a short-term scheduler?.
  1. It selects which process has to be brought into the ready queue
  2. It selects which process has to be executed next and allocates CPU
  3. It selects which process to remove from memory by swapping
  4. None of the mentioned

Answer: b, It selects which process has to be executed next and allocates CPU

Solution: Short-term scheduler selects next process to execute on CPU.

Q26. The primary distinction between the short term scheduler and the long term scheduler is __________.
  1. The length of their queues
  2. The type of processes they schedule
  3. The frequency of their execution
  4. None of the mentioned

Answer: c, The frequency of their execution

Solution: Main difference: frequency (short-term is frequent, long-term less frequent).

Q27. The only state transition that is initiated by the user process itself is __________.
  1. block
  2. wakeup
  3. dispatch
  4. none of the mentioned

Answer: a, block

Solution: Only user-initiated transition is block (e.g., I/O request).

Q28. In a time-sharing operating system, when the time slot given to a process is completed, the process goes from the running state to the __________.
  1. Blocked state
  2. Ready state
  3. Suspended state
  4. Terminated state

Answer: b, Ready state

Solution: Time slice over ? process moves from Running to Ready.

Q29. In a multiprogramming environment __________.
  1. the processor executes more than one process at a time
  2. the programs are developed by more than one person
  3. more than one process resides in the memory
  4. a single user can execute many programs at the same time

Answer: c, more than one process resides in the memory

Solution: Multiprogramming: more than one process resides in memory.

Q30. Suppose that a process is in “Blocked” state waiting for some I/O service. When the service is completed, it goes to the __________.
  1. Running state
  2. Ready state
  3. Suspended state
  4. Terminated state

Answer: b, Ready state

Solution: On I/O completion, process goes from Blocked ? Ready.

Q31. The context of a process in the PCB of a process does not contain __________.
  1. the value of the CPU registers
  2. the process state
  3. memory-management information
  4. context switch time

Answer: d, context switch time

Solution: PCB context excludes context switch time.

Q32. Which of the following does not interrupt a running process?.
  1. A device
  2. Timer
  3. Scheduler process
  4. Power failure

Answer: c, Scheduler process

Solution: Schedulers select processes but do not interrupt running processes.