Why Did the United States Allow West Germany to Become

Why did the United States allow West Germany to become part of a defensive alliance less than ten years after the defeat of Nazi Germany?

A) East Germany had positioned nuclear missiles along the border to the west.
B) The United States depended heavily on the expertise of German rocket scientists.
C) The United States made this concession in order to win access to lucrative German consumer markets.
D) The Soviet detonation of a nuclear bomb underlined the importance of a militarily united West.
E) The United States had thoroughly "de-nazified" the country.