Answer:
b. when plants produce their own sugar
Step-by-step explanation:
Let's look at the products of photosynthesis! During the process of photosynthesis plants break apart the reactants of carbon dioxide and water and recombine them to produce oxygen (O2) and a form of sugar called glucose (C6H12O6).
Glucose provides plants with needed food through a process called photosynthesis. This process helps plants convert the energy they take in from sunlight into sugar to nourish the plant. Photosynthesis occurs when carbon dioxide, water and sunlight are combined. Plants use these to form glucose and oxygen.
Hope this helps!