Question

Which of the following is the main source of free oxygen?

• A. Respiration
• B. Conduction
• C. Photosynthesis
• D. All of the above

Answer 1

Answer: (C)

Photosynthesis

• In plants, during the process of photosynthesis, starch and free oxygen are produced from carbon dioxide and water in the presence of sunlight.

$6C{O}_2+6H_{2}O+$energy $⟶C_6{H}_{12}{O}_6+6O_2$

• During respiration, the plants use free oxygen molecules to produce water, carbon dioxide, and energy, required for plants to grow.
• Conduction is the transfer of heat through matter.
• So, the correct answer is option C.