Answer is option B.Why?
Given algorithm is : After every 'T' time units, processes are given priority w.r.t. waiting time.
lets analyse each option :
(a) not possible. as in FCFS there is no time quantum.
(C) not possible.. SJF is different. It is not preemptive.
(D) In SRTF although a process with shortest burst time is picked. But here priority is assigned based on Burst Time of a process.
The requirement of scheduling algorithm is priority should be assigned based on Waiting Time of a process. Hence this is not the answer.
B is correct.
Ref: https://gateoverflow.in/1419/gate2013-10