18 real Synchronization questions from the Concurrency bank, as asked in Indian campus drives and tech interviews. Every question has a verified answer and an AI-tutor explanation on placd — free to start.
1. What is Mutex?
Junior
A.a region of code that accesses shared state and must be executed by only one thread at a time to remain correct
B.a locking primitive that grants exclusive access to a resource to one holder at a time, requiring the same holder to release it
C.a mutual-exclusion device that the same holder may acquire repeatedly without blocking itself, releasing only after a matching number of releases
D.a high-level construct bundling shared data with the procedures that operate on it under automatic mutual exclusion, often paired with condition variables
2. Which term means: "a locking primitive that grants exclusive access to a resource to one holder at a time, requiring the same holder to release it"?
A.Mutex — a mutual-exclusion device that the same holder may acquire repeatedly without blocking itself, releasing only after a matching number of releases
B.Mutex — a locking primitive that grants exclusive access to a resource to one holder at a time, requiring the same holder to release it
C.Mutex — a primitive allowing many concurrent readers but only one exclusive writer, optimizing for read-heavy shared data
D.Mutex — a region of code that accesses shared state and must be executed by only one thread at a time to remain correct
5. Which term means: "a counter-based signaling primitive that permits up to N simultaneous accessors and can be signaled by any party, not only the acquirer"?
A.Semaphore — a high-level construct bundling shared data with the procedures that operate on it under automatic mutual exclusion, often paired with condition variables
B.Semaphore — a primitive allowing many concurrent readers but only one exclusive writer, optimizing for read-heavy shared data
C.Semaphore — a locking primitive that grants exclusive access to a resource to one holder at a time, requiring the same holder to release it
D.Semaphore — a counter-based signaling primitive that permits up to N simultaneous accessors and can be signaled by any party, not only the acquirer
A.Critical section — a high-level construct bundling shared data with the procedures that operate on it under automatic mutual exclusion, often paired with condition variables
B.Critical section — a locking primitive that grants exclusive access to a resource to one holder at a time, requiring the same holder to release it
C.Critical section — a region of code that accesses shared state and must be executed by only one thread at a time to remain correct
D.Critical section — a mutual-exclusion device that the same holder may acquire repeatedly without blocking itself, releasing only after a matching number of releases
A.a mutual-exclusion device that the same holder may acquire repeatedly without blocking itself, releasing only after a matching number of releases
B.a primitive allowing many concurrent readers but only one exclusive writer, optimizing for read-heavy shared data
C.a locking primitive that grants exclusive access to a resource to one holder at a time, requiring the same holder to release it
D.a high-level construct bundling shared data with the procedures that operate on it under automatic mutual exclusion, often paired with condition variables
11. Which term means: "a high-level construct bundling shared data with the procedures that operate on it under automatic mutual exclusion, often paired with condition variables"?
A.Monitor — a high-level construct bundling shared data with the procedures that operate on it under automatic mutual exclusion, often paired with condition variables
B.Monitor — a region of code that accesses shared state and must be executed by only one thread at a time to remain correct
C.Monitor — a mutual-exclusion device that the same holder may acquire repeatedly without blocking itself, releasing only after a matching number of releases
D.Monitor — a locking primitive that grants exclusive access to a resource to one holder at a time, requiring the same holder to release it
A.a mutual-exclusion device that the same holder may acquire repeatedly without blocking itself, releasing only after a matching number of releases
B.a locking primitive that grants exclusive access to a resource to one holder at a time, requiring the same holder to release it
C.a region of code that accesses shared state and must be executed by only one thread at a time to remain correct
D.a high-level construct bundling shared data with the procedures that operate on it under automatic mutual exclusion, often paired with condition variables
14. Which term means: "a mutual-exclusion device that the same holder may acquire repeatedly without blocking itself, releasing only after a matching number of releases"?
A.Reentrant lock — a region of code that accesses shared state and must be executed by only one thread at a time to remain correct
B.Reentrant lock — a mutual-exclusion device that the same holder may acquire repeatedly without blocking itself, releasing only after a matching number of releases
C.Reentrant lock — a primitive allowing many concurrent readers but only one exclusive writer, optimizing for read-heavy shared data
D.Reentrant lock — a counter-based signaling primitive that permits up to N simultaneous accessors and can be signaled by any party, not only the acquirer
A.a primitive allowing many concurrent readers but only one exclusive writer, optimizing for read-heavy shared data
B.a counter-based signaling primitive that permits up to N simultaneous accessors and can be signaled by any party, not only the acquirer
C.a region of code that accesses shared state and must be executed by only one thread at a time to remain correct
D.a high-level construct bundling shared data with the procedures that operate on it under automatic mutual exclusion, often paired with condition variables
A.Read-write lock — a high-level construct bundling shared data with the procedures that operate on it under automatic mutual exclusion, often paired with condition variables
B.Read-write lock — a primitive allowing many concurrent readers but only one exclusive writer, optimizing for read-heavy shared data
C.Read-write lock — a counter-based signaling primitive that permits up to N simultaneous accessors and can be signaled by any party, not only the acquirer
D.Read-write lock — a region of code that accesses shared state and must be executed by only one thread at a time to remain correct
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