Question

level 5
q3
plants made the oxygen in the air animals use to breath by
a. splitting apart water molecules
b. splitting apart carbon dioxide
c. attaching water together
d. attaching oxygen together

○ a. splitting apart water molecules
○ b. splitting apart carbon dioxide
○ c. attaching water together
○ d. attaching oxygen together

Explanation:

In photosynthesis, plants produce oxygen by splitting water molecules ($\ce{H_2O}$) during the light - dependent reactions. Carbon dioxide is used to make glucose, not to produce oxygen by splitting. Attaching water or oxygen together does not produce the oxygen we breathe. So the correct option is A.

Answer:

A. Splitting apart water molecules