What is the critical path and time duration?A simple CPM network has three activities, A, B, and C. A is an immediate predecessor of B and of C. B is an immediate predecessor of C. The activity durations are A=4, B=3, C=8.(A) The critical path is A-B-C, duration 15.(B) The critical path is A-C, duration 12.(C) The critical path is A-B-C, duration 13.5(D) The critical path cannot be determined withoutknowing PERT expected activity times.(E) The network has no critical path.