What are chloroplasts responsible for in plants?

Chloroplasts are specialized organelles found in plant cells that are primarily responsible for photosynthesis, the process by which plants convert light energy into chemical energy. During photosynthesis, chloroplasts capture sunlight using the green pigment chlorophyll and harness it to transform carbon dioxide and water into glucose and oxygen. This process is crucial for plants as it provides them with the energy necessary for growth and development, while also producing oxygen, which is essential for most life forms on Earth.

The other options do not accurately describe the main function of chloroplasts. While water storage is typically a function of the vacuole, and cell division occurs in other cellular components like the nucleus, protein synthesis primarily takes place in ribosomes. Thus, the specific role of chloroplasts in photosynthesis distinguishes them as integral to plant life and energy production.