Which Planet May Have Helium Rain in Its Interior,and What

Multiple Choice

Which planet may have helium rain in its interior,and what does this rain do?

A) Uranus,where it makes the ground wet.
B) Neptune,where it is restructuring the planet's interior.
C) Jupiter,where it may be an energy source for the Great Red Spot.
D) Saturn,where it generates heat as it falls downward.