Fetch_And_Add (X, i) is an atomic Read-Modify-Write instruction that reads the value of memory location X, increments it by the value i and returns the old value of X. It is used in the pseudocode shown below to implement a busy-wait lock. L is an unsigned integer shared variable initialized to 0. The value of 0 corresponds to lock being available, while any non-zero value corresponds to the lock being not available.AcquireLock (L) { while (Fetch_And_Add (L, 1)) L = 1; } ReleaseLock (L) { L = 0 } This implementation

works correctly but may starve some processes

fails as L can take on a non-zero value that lock is actually available

works correctly but may starve some processes

works correctly without starvation

Fetch_And_Add (X, i) is an atomic Read-Modify-Write instruction that r

1.	Fetch_And_Add (X, i) is an atomic Read-Modify-Write instruction that reads the value of memory location X, increments it by the value i and returns the old value of X. It is used in the pseudocode shown below to implement a busy-wait lock. L is an unsigned integer shared variable initialized to 0. The value of 0 corresponds to lock being available, while any non-zero value corresponds to the lock being not available.AcquireLock (L) { while (Fetch_And_Add (L, 1)) L = 1; } ReleaseLock (L) { L = 0 } This implementation
A.	fails as L can overflow
B.	fails as L can take on a non-zero value that lock is actually available
C.	works correctly but may starve some processes
D.	works correctly without starvation
Answer» C. works correctly but may starve some processes

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