Threading and Multithreading MCQs: Concepts and Implementation

Questions (30)

1. What is a thread in the context of operating systems?

   • a) A process that runs in isolation
   • b) The smallest unit of execution within a process
   • c) A collection of processes sharing resources
   • d) A virtual representation of system memory
   View Answer

   Correct The smallest unit of execution within a process

2. Which of the following best describes multithreading?

   • a) Running multiple processes simultaneously
   • b) Running multiple threads within a single process
   • c) Allocating memory to different programs
   • d) Scheduling tasks in sequential order
   View Answer

   Correct Running multiple threads within a single process

3. What is the main advantage of using multithreading in applications?

   • a) Improved memory usage
   • b) Faster single-threaded performance
   • c) Increased responsiveness and parallelism
   • d) Reduced CPU usage
   View Answer

   Correct Increased responsiveness and parallelism

4. What is a key challenge of multithreading?

   • a) Memory allocation issues
   • b) Synchronization and avoiding race conditions
   • c) Low processor utilization
   • d) Redundant resource usage
   View Answer

   Correct Synchronization and avoiding race conditions

5. Which of the following is an example of thread-safe operation?

   • a) Reading from a shared variable without locks
   • b) Modifying shared data with proper synchronization
   • c) Writing to global memory without checks
   • d) Accessing a file without considering concurrent threads
   View Answer

   Correct Modifying shared data with proper synchronization

6. In Java, which class is commonly used to create threads?

   • a) ThreadPool
   • b) Thread
   • c) Runnable
   • d) Executor
   View Answer

   Correct Thread

7. What is the state of a thread when it is waiting for a resource?

   • a) Running
   • b) Waiting
   • c) Terminated
   • d) Blocked
   View Answer

   Correct Blocked

8. What does context switching refer to in multithreading?

   • a) Switching between user and kernel modes
   • b) Switching the CPU's focus between threads
   • c) Allocating resources to a process
   • d) Synchronizing shared memory
   View Answer

   Correct Switching the CPU's focus between threads

9. Which threading model maps multiple threads to multiple processors?

   • a) One-to-one model
   • b) Many-to-one model
   • c) Many-to-many model
   • d) Kernel-level model
   View Answer

   Correct Many-to-many model

10. What mechanism prevents two threads from accessing shared resources simultaneously?

    • a) Semaphore
    • b) Mutex
    • c) Critical section
    • d) All of the above
    View Answer

    Correct All of the above

11. In Python, which module is used for creating threads?

    • a) multiprocessing
    • b) threading
    • c) asyncio
    • d) concurrent.futures
    View Answer

    Correct threading

12. Which of the following is not a thread state?

    • a) Ready
    • b) Waiting
    • c) Running
    • d) Suspended
    View Answer

    Correct Suspended

13. What is a race condition?

    • a) A condition where threads compete for CPU time
    • b) A scenario where the outcome depends on the thread execution order
    • c) A type of thread-safe execution
    • d) An error in thread termination
    View Answer

    Correct A scenario where the outcome depends on the thread execution order

14. What is the primary use of a thread pool?

    • a) To allocate memory to processes
    • b) To manage multiple threads efficiently
    • c) To handle file I/O operations
    • d) To synchronize thread execution
    View Answer

    Correct To manage multiple threads efficiently

15. Which of the following is a lightweight process?

    • a) Thread
    • b) Task
    • c) Process
    • d) Job
    View Answer

    Correct Thread

16. Deadlock in multithreading occurs when:

    • a) Threads execute simultaneously
    • b) Threads wait indefinitely for resources held by each other
    • c) Thread priorities are ignored
    • d) All threads terminate normally
    View Answer

    Correct Threads wait indefinitely for resources held by each other

17. The term "thread priority" refers to:

    • a) The order of thread execution based on importance
    • b) The speed of thread execution
    • c) The memory allocated to threads
    • d) The total number of active threads
    View Answer

    Correct The order of thread execution based on importance

18. What is a daemon thread in Java?

    • a) A thread that runs in the background and terminates when the program ends
    • b) A thread that handles user requests
    • c) A thread that prevents deadlocks
    • d) A thread with the highest priority
    View Answer

    Correct A thread that runs in the background and terminates when the program ends

19. Which of these is not a synchronization mechanism?

    • a) Semaphore
    • b) Monitor
    • c) Mutex
    • d) Context switch
    View Answer

    Correct Context switch

20. In C++, which library provides support for multithreading?

    • a) std::thread
    • b) pthreads
    • c) OpenMP
    • d) All of the above
    View Answer

    Correct All of the above

21. What is the primary purpose of a lock in multithreading?

    • a) To increase execution speed
    • b) To prevent simultaneous access to shared resources
    • c) To allow threads to communicate
    • d) To reduce memory usage
    View Answer

    Correct To prevent simultaneous access to shared resources

22. What does GIL stand for in Python threading?

    • a) Global Instruction Lock
    • b) Global Interpreter Lock
    • c) General Incremental Lock
    • d) Generic Interface Library
    View Answer

    Correct Global Interpreter Lock

23. Which scheduling algorithm is commonly used in multithreading?

    • a) First-Come-First-Served
    • b) Round-Robin
    • c) Shortest Job Next
    • d) Longest Job First
    View Answer

    Correct Round-Robin

24. Which of the following is a disadvantage of multithreading?

    • a) Increased resource utilization
    • b) Simplified program logic
    • c) Increased complexity in debugging
    • d) Enhanced responsiveness
    View Answer

    Correct Increased complexity in debugging

25. The main thread in a multithreaded program is:

    • a) The thread that creates child threads
    • b) A background thread
    • c) The last thread to terminate
    • d) A low-priority thread
    View Answer

    Correct The thread that creates child threads

26. Which of the following can cause a thread to terminate?

    • a) Completing its task
    • b) Calling the terminate() function
    • c) Receiving a signal from the operating system
    • d) All of the above
    View Answer

    Correct All of the above

27. What is thread starvation?

    • a) Threads being unable to access shared memory
    • b) High-priority threads preventing low-priority threads from executing
    • c) Threads competing for CPU resources
    • d) Synchronization mechanisms failing
    View Answer

    Correct High-priority threads preventing low-priority threads from executing

28. Thread-local storage is used for:

    • a) Sharing memory between threads
    • b) Storing data unique to each thread
    • c) Allocating memory to all threads
    • d) Managing thread priorities
    View Answer

    Correct Storing data unique to each thread

29. Which of the following conditions is necessary for a deadlock to occur?

    • a) Circular wait
    • b) Mutual exclusion
    • c) Hold and wait
    • d) All of the above
    View Answer

    Correct All of the above

30. What is the main goal of thread synchronization?

    • a) To ensure threads execute in order of creation
    • b) To prevent conflicts and inconsistencies in shared resources
    • c) To allocate CPU time equally among threads
    • d) To improve memory allocation efficiency
    View Answer

    Correct To prevent conflicts and inconsistencies in shared resources