Which of the following is a product of photosynthesis?

A. Carbon dioxide

B. Sunlight

C. Water

D. Oxygen

Answer is D.

Photosynthesis is a process which converts the energy in light into chemical energy in compounds. This process happens inside the living organisms which have chlorophylls. With the presence of sunlight and chlorophylls, organisms which can do photosynthesis produce glucose and oxygen as products by using carbon dioxide and water as materials.

Reaction is

6CO ₂ (g) + 6H₂O (l) → C₆H₁₂O₆ (s) + 6O₂ (g)

The answer is D. Oxygen. The photosynthesis is a process through which green plants uses the energy from sunlight to convert Carbon Dioxide and water into energy molecule (glucose). Oxygen is also produced as as product of this process.