In the hospital project network, which activity has immediate predecessors C and F?

• A. H
• B. J
• C. K
• D. G

Answer: (D)

In a project network, an activity can start only after all of its immediate predecessors are finished. If an activity has C and F as its immediate predecessors, it must wait for both C and F to complete, and its earliest start time is the later of the two finish times.

In the hospital network, the activity that begins only after both C and F are finished is the one that depends on both of them. That is why this is the correct choice—the activity that has C and F as its immediate predecessors. Other activities would have either only one of those predecessors or different prerequisites, so they wouldn’t meet the requirement of having both C and F as immediate predecessors.