Each of a set of n processes executes the following code using two semaphores a and b initialized to 1 and 0, respectively. Assume that count is a shared variable initialized to 0 and not used in CODE SECTION P.CODE SECTION Pwait (a); count=count+1 ;if (count==n) signal (b) ;signal (a) ; wait (b) ; signal (b) ;CODE SECTION QWhat does the code achieve?

It ensures that at most two processes are in CODE SECTION Q at any time.

It ensures that no process executes CODE SECTION Q before every process has finished CODE SECTION P.

It ensures that all processes execute CODE SECTION P mutually exclusively.

It ensures that at most n-1 processes are in CODE SECTION P at any time.

Each of a set of n processes executes the following code using two sem

1.	Each of a set of n processes executes the following code using two semaphores a and b initialized to 1 and 0, respectively. Assume that count is a shared variable initialized to 0 and not used in CODE SECTION P.CODE SECTION Pwait (a); count=count+1 ;if (count==n) signal (b) ;signal (a) ; wait (b) ; signal (b) ;CODE SECTION QWhat does the code achieve?
A.	It ensures that no process executes CODE SECTION Q before every process has finished CODE SECTION P.
B.	It ensures that at most two processes are in CODE SECTION Q at any time.
C.	It ensures that all processes execute CODE SECTION P mutually exclusively.
D.	It ensures that at most n-1 processes are in CODE SECTION P at any time.
Answer» B. It ensures that at most two processes are in CODE SECTION Q at any time.

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