You know that there are bodies of water. Did you also know that there are bodies of air? Not all air is the same—some is hot, some is cold, some is dry, and some is humid. A large body of air with the same temperature and humidity throughout is called an air mass.
What is a MAIN point of this paragraph?
A) An air mass is made up of air with different temperatures.
B) There are a lot of bodies of water but only one kind of body of air.
C) An air mass is always a body of hot, dry air.
D) Just as there are bodies of water, there are bodies of air.