Which of the following is true for both outer gas planets and inner terrestrial planets? their orbits are inside the asteroid belt. they have rings. they have a round shape. they have a core of ice.

They have a round shape

Explanation:

The gas giants which are the outer planets, and the terrestrial planets which are the inner ones have lot of differences between them. They have different sizes, different composition, different atmospheres, temperatures etc. But they also have something in common, which is pretty much the most obvious thing, they all have round shape. All of the planets have round shape, or rather they are slightly elliptical as they are more elongated around their equators, and slightly more flattened around their poles. This kind of shape has occurred because of these planets spin around their own axis, and around the Sun, thus the surface has become much smoother over time because of the friction.

the entire statement is true and correct.  

there's no diagram, nothing is illustrated, and no question is asked.