Answer (d)
Since we need to find the max process in CS.
We will find a case in which maximum process can be in CS.
Let’s say P1,P2….P9 started to execute. [DOWN()]
P1: Will go to CS and mutex value will be change to 0. [ mutex=0 ]
Rest of the Processes [P2,P3…..P9 ] will be blocked as mutex is 0 and will be put in the blocked Q.
Now ,
P10 will start its execution and it will perform 2 UP() operations while going 1 time through the CS.
As it says, process can execute any number of times.
So, P10 can execute any number of times.
Each time when UP() will be performed it will wake up 1 Process from the Blocked Q ..
and woken up Process can go to CS
after sometime Blocked Q will be empty.
And at one point of time all process P1,P2,P3….P10 will be in CS.