Why Does the Power of the President Increase Most Dramatically

Why does the power of the president increase most dramatically in wartime?

A) The president makes more efficient decisions necessary for war.
B) Soldiers vote for the president in power during wars.
C) Congress has trouble raising money and relies on the president in wartime.
D) Drafting soldiers increases a president's popularity during wartime.
E) Free riding decreases Congress's power for waging war.