The correct answer is option-1: chloroplasts. Chloroplasts are cell organelles that are responsible for photosynthesis, the process by which plants convert sunlight into energy. They are found in the cells of plants, algae, and some bacteria.

One of the main functions of chloroplasts is to contain chlorophyll, a pigment that gives plants their green color. Chlorophyll is essential for capturing light energy from the sun and converting it into chemical energy during the process of photosynthesis.

Option-2: vacuole is incorrect as the vacuole is a large membrane-bound sac found in plant and fungal cells that stores water, nutrients, and waste products. It does not play a direct role in photosynthesis.

Option-3: cytoplasm is incorrect as the cytoplasm is a jelly-like substance that fills the cell and contains various organelles, including the chloroplasts. While the cytoplasm helps support the organelles, it is not the specific site of photosynthesis.

Option-4: nucleolus is incorrect as the nucleolus is a suborganelle found within the nucleus of eukaryotic cells and is involved in the production of ribosomes. It does not have any role in photos