A project manager is reviewing a task list for a new software release. The table below shows each task, its estimated duration, and its prerequisite tasks. All durations are in days. What is the minimum number of days required to complete Task F, assuming all tasks can be parallelized when prerequisites are met?

✓ Correct Answer: Option C

To complete Task F, both Task C (5 days) and Task E (8 days) must be done. Task C depends on A (4 days) and B (3 days). Task E depends on D (7 days) and B (3 days). The critical path to F is A (4) -> C (5) -> F (9) = 18 days, OR D (7) -> E (8) -> F (9) = 24 days. No, let's re-evaluate. The path is: A->C (4+5=9). B is a pre-req for C and E. D->E (7+8=15). Critical path to F is the max of (path to C + F) and (path to E + F). Path to C = max(A, B) + C = max(4,3)+5 = 4+5 = 9. Path to E = max(B, D) + E = max(3,7)+8 = 7+8 = 15. So, Task F can start after 15 days, and F itself takes 3 days. This makes 15+3=18 days. Let's check again: A(4), B(3), D(7). Task C needs A & B: Max(4,3)+5 = 9. Task E needs B & D: Max(3,7)+8 = 15. Task F needs C & E: Max(9,15)+3 = 18. So 18 days.