Who is the Commander in Chief of the military?

Why this is the answer

The President is the Commander in Chief of the military. That was a choice, not an accident: the Founding Fathers wanted the armed forces headed by a civilian chosen by the people rather than by a professional military leader, which follows from the republican idea that political power comes from the citizens. The power is not unlimited. The President commands the forces, but Congress pays for them and holds the power to declare war. In 1973 Congress went further and passed the War Powers Act, giving itself a stronger voice in decisions about sending troops; the President vetoed it and Congress overrode the veto. Memory hook: a civilian commands the military, and Congress holds the purse and the power to declare war.