There are three processes P1, P2 and P3 sharing a semaphore for synchronising a variable. Initial value of semaphore is one. Assume that negative value of semaphore tells us how many processes are waiting in queue. Processes access the semaphore in following order: (a) P2 needs to access (b) P1 needs to access (c) P3 needs to access (d) P2 exits critical section (e) Pi exits critical section The final value of semaphore will be: (1) 0 (2) 1 (3) -1 (4) -2 

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