Answer is (D)
Set Mutex = 1
V(mutex) -> increment value of mutex
P(mutex) -> decrement value of mutex
Process enters into CS only when mutex = 1
P10 enters
mutex = 1 {P10}
P1 enters
mutex = 0 {P10,P1}
P10 exits
mutex = 1 {P1}
P10 enters
mutex = 1 {P1,P10}
P2 enters
mutex = 0 {P10,P1,P2}
P10 exits
mutex = 1 {P1,P2}
P10 enters
mutex = 1 {P1,P2,P10}
P3 enters
mutex = 0 {P10,P1,P2,P3}
P10 exits
mutex = 1 {P1,P2,P3}
P10 enters
mutex = 1 {P1,P2,P3,P10}
....
P9 enters
mutex = 0 { P10,P1,P2 ... P9 }
P10 exits
mutex = 1 {P1 ... P9}
P10 enters
mutex = 1 {P1,P2.... P9,P10}
So maximum 10 process in Critical section at a specific time period.
Options D