Imagine That You Could Magically Move the Moon Closer to Earth

Multiple Choice

Imagine that you could magically move the moon closer to Earth, so that the distance from Earth to moon is cut in half. This would cause the force that Earth exerts on the moon to be

A) increased to four times its original value.
B) doubled.
C) reduced to 1/4 of its original value.
D) halved.
E) Nonsense-- Earth exerts no force on the moon.