Clean air
A) is pure oxygen.
B) contains mostly oxygen, some nitrogen and nothing else.
C) contains mostly nitrogen, some oxygen and nothing else.
D) contains mostly nitrogen, some oxygen, and a very small amount of several other gases.
E) has all of its nitrogen removed.

Question

Quizplus · Accepted Answer

Clean air contains mostly nitrogen and oxygen, but also trace amounts of several other gases such as carbon dioxide, helium, and neon. Therefore, option D is the best choice. Options A, B, and E are not accurate as they either simplify the composition of air or completely remove one of its main components. Option C is incorrect as nitrogen actually makes up a larger percentage of clean air than oxygen.

Clean Air