The Next Three Questions Relate to the Following Scenario: Erica

The next three questions relate to the following scenario: Erica is planning a large surprise party for her best friend. She has developed the plan below which includes estimates of the time in hours) and cost necessary to perform each of the activities required.
$$\begin{array} { | l | c | c | c | c | c | } \hline \text { Activity } & \text { Predeces sor } & \begin{array} { c } \text { Normal } \\\text { Time } \\\text { (hrs) }\end{array} & \begin{array} { c } \text { Crash } \\\text { Time } \\\text { (hrs) }\end{array} & \begin{array} { c } \text { Norm al } \\\text { Cost }\end{array} & \begin{array} { c } \text { Crash } \\\text { Cost }\end{array} \\\hline \text { A. Create Guest List } & - - & 8 & 4 & \$ 200 & \$ 310 \\\hline \text { B. Send Invitations } & \text { A } & 2 & 1 & \$ 125 & \$ 150 \\\hline \text { C. Plan Decorations } & \text { A } & 8 & 6 & \$ 300 & \$ 370 \\\hline \text { D. Plan Menu } & \text { A } & 3 & 2 & \$ 150 & \$ 210 \\\hline \text { E. Shop } & \text { D } & 4 & 2 & \$ 475 & \$ 550 \\\hline \text { F. Prepare Food } & \text { E } & 5 & 3 & \$ 225 & \$ 475 \\\hline\end{array}$$

-Erica's internet-based business pays her about $40 per hour. Therefore, for every hour she works on this party project, she will experience a lost opportunity cost of $40. She would initially like to test the idea of reducing project duration by one hour. Which activity should she crash first?

A) A
B) D
C) C
D) E
E) B