Two Critical Path Activities Are Candidates for Crashing on a CPM

Two critical path activities are candidates for crashing on a CPM network. Activity details are in the table below. To cut one day from the project's duration, activity ________ should be crashed first, adding ________ to project cost. $$\begin{array} { | c | c | c | c | c | } \hline \text { Activity } & \text { Normal Time } & \text { Normal Cost } & \text { Crash Time } & \text { Crash Cost } \\\hline \mathrm { D } & 5 \text { days } & \$ 6,000 & 3 \text { days } & \$ 8,000 \\\hline \mathrm { E } & 8 \text { days } & \$ 4,000 & 4 \text { days } & \$ 6,000 \\\hline\end{array}$$

A) D; $2,000
B) D; $1,000
C) E; $500
D) E; $2,000
E) E; $6,000