Which of the following is a by-product of photosynthesis?

A) carbon dioxide
B) water
C) oxygen
D) glucose
E) energy

Photosynthesis

A biochemical process in green plants and certain other organisms that converts light energy into chemical energy, using carbon dioxide and water to produce glucose and oxygen.

By-product

A secondary product generated as a result of a manufacturing process, chemical reaction, or biological pathway, which was not the primary product or goal.