Critical path

Time, resource and relationships for a project:

Which activity or activities are on the critical path?

(More than one is correct).

A

B

C

D

E

\begin{tabular}{|c|c|c|c|} \hline Activity & Predecessor & Duration & Resources \\ \hline A & None & 2 & 3 \\ \hline B & A & 1 & 2 \\ \hline C & A & 5 & 1 \\ \hline D & B and C & 3 & 3 \\ \hline E & D & 4 & 1 \\ \hline \end{tabular}