The correct answer is A. Photosynthesis.
Chloroplasts are organelles found in plant cells that are responsible for photosynthesis. Photosynthesis is the process by which plants use sunlight to convert carbon dioxide and water into glucose and oxygen. Glucose is a type of sugar that plants use for energy. Oxygen is a gas that is released into the atmosphere.
Option B is incorrect because chloroplasts are not responsible for storage. Storage is the process by which cells store nutrients and other materials. Chloroplasts do not store nutrients or other materials.
Option C is incorrect because chloroplasts are not responsible for cell movement. Cell movement is the process by which cells move around. Chloroplasts do not move around.
Option D is incorrect because chloroplasts are not responsible for respiration. Respiration is the process by which cells break down glucose to produce energy. Chloroplasts do not break down glucose to produce energy.