In a network diagram an activity:A. should always be something the company has h

In a network diagram an activity:A. should always be something the company has had experiencewith.B. must always have a single precise estimate for the timeduration.C. is the largest unit of work effort consuming both time andresources that a project manager can schedule and control.D. is the smallest unit of work effort consuming both timeand resources that a project manager can schedule and control.