If the Organizers wants to ensure that all routes from S to T get the same number of participants, then a feasible set of task time (in hours) at junctions A, B, C, and D respectively to achieve this goal is:
1,5,3,2
To ensure that all the routes from S to T get the same number of participants, Going by the answer options
As the time must be same for all the routes, it must be option (d).