1) If a project is to be crashed at the minimum possible additional cost, then the first activity to be crashed must be: On the critical path B. the...

1)    If a project is to be crashed at the minimum possible additional cost, then the first activity to be crashed must be:

A. On the critical path

B. the one with the shortest activity time.

C. the one with the longest activity time.

D. the one with the lowest cost.

Can you please tell me which one is the correct answer and why?