The process by which green plants prepare their own food is known as :

1. Photorespiration
2. Photolysis
3. Photosynthesis
4. None of the above

Photosynthesis

Reason — Photosynthesis is the process by which green plants capture solar energy and use it to convert carbon dioxide and water into simple sugars (glucose).
Photorespiration is a wasteful process where oxygen is taken in and carbon dioxide is released. It does not produce food; instead, it reduces the efficiency of photosynthesis. Photolysis refers to the splitting of water molecules using light energy during photosynthesis. It is just a step within photosynthesis, not the whole process of making food.