Gas released during photosynthesis is

Methane
Nitrogen
Oxygen
Carbon dioxide

The correct answer is C. Oxygen.

Photosynthesis is the process by which plants use sunlight, water, and carbon dioxide to create oxygen and energy in the form of sugar. The chemical equation for photosynthesis is:

6CO2 + 6H2O + light energy → C6H12O6 + 6O2

As you can see from the equation, oxygen is one of the products of photosynthesis. It is released into the atmosphere through the stomata, which are small pores on the surface of leaves.

Methane is a gas that is produced by the decomposition of organic matter. It is a greenhouse gas that contributes to climate change.

Nitrogen is a gas that makes up about 78% of the atmosphere. It is essential for plant growth, but it is not produced by photosynthesis.

Carbon dioxide is a gas that is released into the atmosphere when plants respire. It is also a greenhouse gas that contributes to climate change.

I hope this helps!