PLEASE HELP
Why are the outer planets sometimes called gas giants?
A) The outer planets are called gas giants because they have volcanos that give off gas.
B) The outer planets are called gas giants because they are named after giant beings from Greek mythology.
C) The outer planets are often called gas giants because they are very large and emit gases from their cores.
D) The outer planets are often called gas giants because they are composed almost entirely of gas and are much larger than any of the four inner planets.
