Buoyancy: a Cup of Water Containing an Ice Cube at 0°C

Buoyancy: A cup of water containing an ice cube at 0°C is filled to the brim. The tip of the ice cube sticks out of the surface. As the ice melts, you observe that

A) the cup overflows.
B) the cup might overflow but it depends on the actual mass of the ice cube.
C) the water level remains the same.
D) the water level actually goes down.
E) There is not enough information to answer this question.