What is the main role of chloroplasts in plant cells?

Chloroplasts play a crucial role in plant cells primarily by conducting photosynthesis. This process allows plants to convert light energy, typically from the sun, into chemical energy stored in glucose, which is a sugar. The chloroplasts contain the green pigment chlorophyll, which absorbs light energy needed for this reaction. Photosynthesis occurs in two main stages: the light-dependent reactions and the light-independent reactions (Calvin cycle).

In the light-dependent reactions, chloroplasts capture solar energy and use it to split water molecules, releasing oxygen and generating energy-rich molecules like ATP and NADPH. These energy carriers are then used in the Calvin cycle to convert carbon dioxide into glucose.

This function of chloroplasts is essential for the survival of the plant and for the entire ecosystem, as it provides the organic compounds and oxygen essential for other forms of life. In summary, chloroplasts are specialized organelles responsible for the conversion of light energy into chemical energy through the process of photosynthesis, making option C the correct choice.