Consider the Following Work Breakdown Structure What Is the Estimated Slack Time for Activity D?
A)

Consider the following work breakdown structure: $\begin{array}{cccccc}&\text { Start }&\text { Finish }&&\text { Duration (Days) } \\\text { Activity } & \text { Node } & \text { Node } & \text { Optimistic } & \text { Most Likely } & \text { Pessimistic } \\\hline \text { A } & 1 & 2 & 41 & 50 & 59 \\\text { B } & 1 & 3 & 54 & 60 & 66 \\\text { C } & 2 & 4 & 58 & 70 & 82 \\\text { D } & 3 & 4 & 32 & 41 & 44\end{array}$ What is the estimated slack time for activity D?

A) 0 days
B) 19 days
C) 20 days
D) 79 days
E) 80 days