Hi There!
Answer - B. Gases and solids
Why - The atmosphere is made up of different gases like carbon dioxide and nitrogen, the solid like dust particles.
Hope This Helps :)
The answer is C because of the fact Earth's atmosphere is 78% nitrogen, 21% oxygen, 0.9% argon, and 0.03% carbon dioxide and also contains water vapor. It does have a few dust particles and whatnot