How much oxygen does the
atmosphere contain?
O 12%
0 76%
O 35%
0 26%

20.95%

Explanation:

By volume, dry air contains 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.04% carbon dioxide, and small amounts of other gases. Air also contains a variable amount of water vapor, on average around 1% at sea level, and 0.4% over the entire atmosphere.

answer; the correct answer is desert plants;

i believe it would cause an increase of percipitation, though i could be wrong. so i would say b is the answer.