Which One of the Following Four Statements Applies to All

Multiple Choice

Which one of the following four statements applies to all four of the Jovian planets?

A) Liquid metallic hydrogen makes up a large part of their interiors.
B) Their spin axes are approximately perpendicular to their orbital planes.
C) They are almost entirely hydrogen and helium: Only about 1% of their mass is made up of heavier elements.
D) They are all thought to have a substantial rocky core.