Question

Photosynthesis is _____.

Answer 1

The answer here would be number 3, photosynthesis can e explained with the equation  carbon dioxide + water —> glucose + oxygen + water, this means that plants use light to convert carbon dioxide into carbohydrates or as you put it enery rich glucose molecules, this is the way plants make there food 

Answer 2

Answer: The correct answer for the blank is-

3) The use of light energy to convert water and carbon dioxide into energy-rich glucose molecules.

Photosynthesis is process of formation of food ( glucose) in green plants and algae using carbon dioxide and water in the presence of sunlight.

In the first phase ( a light dependent phase), a green pigment called chlorophyll ( present in the chloroplast of plants and algae) first absorbs the energy from sunlight and converts it into chemical energy in the form of ATP, and NADPH.

This energy is then utilized in the formation of energy rich glucose molecule in the next phase, which is a light independent phase.

Thus, option 3) is the right answer.