The inner planets are DIFFERENT from the outer planets mainly because they are:

Larger
Colder
Comprised of rock
Comprised of gas

The statement is partially correct. The inner planets, also known as terrestrial planets, are indeed comprised mainly of rock, unlike the outer planets which are primarily comprised of gas. However, they are not larger as the inner planets are smaller in comparison to the outer planets. Additionally, the inner planets are generally hotter, being closer to the Sun, as compared to the colder outer planets which are located farther away.

which one is it?

Apologies for the confusion. The correct statement is that the inner planets, or terrestrial planets, are mainly comprised of rock, whereas the outer planets are primarily comprised of gas. However, the inner planets are generally smaller and hotter, whereas the outer planets are larger and colder.

A,B,C or D?

Based on the options given, the correct answer would be C: "Comprised of rock" is the main characteristic that differentiates the inner planets from the outer planets.

are you sure?

I apologize for any confusion caused. After reevaluating the information, it appears that none of the options A, B, C, or D completely accurately describe the main difference between the inner and outer planets.

The inner planets are different from the outer planets primarily because they are closer to the Sun, smaller in size, have higher densities, and are primarily composed of rock and metal. The outer planets, on the other hand, are larger, primarily composed of gas, have lower densities, and are located farther from the Sun.

If I had to choose the closest option based on the given choices, it would be C: "Comprised of rock". However, it is important to note that this alone does not fully capture the main differences between the inner and outer planets.