What type of energy does a plant use to convert \( \mathrm{CO_2} \) and \( \mathrm{H_2O} \) into sugar during photosynthesis?

• A. Chemical energy
• B. Mechanical energy
• C. Light energy
• D. Thermal energy

Answer: (C)

Verified step by step guidance

1. Understand the process of photosynthesis: Photosynthesis is the process by which plants convert carbon dioxide ( ${\mathrm{CO}}_2$ ) and water ( $H_{2}O$ ) into glucose (sugar) and oxygen using energy from sunlight.
2. Identify the type of energy involved: Plants use light energy, which is absorbed by chlorophyll pigments in the chloroplasts, to drive the chemical reactions of photosynthesis.
3. Relate light energy to the chemical reaction: Light energy is converted into chemical energy during the light-dependent reactions of photosynthesis. This energy is stored in molecules like ATP and NADPH.
4. Understand the role of light energy: Light energy is essential for splitting water molecules ( $H_{2}O$ ) into oxygen, protons, and electrons, which are then used in the synthesis of glucose.
5. Conclude the correct answer: Based on the process of photosynthesis, the type of energy used by plants to convert ${\mathrm{CO}}_2$ and $H_{2}O$ into sugar is light energy.