What is the primary function of chlorophyll in plants?

Chlorophyll's primary function in plants is the absorption of sunlight. This pigment is critical for photosynthesis, the process by which plants convert light energy into chemical energy. Chlorophyll primarily absorbs light in the blue and red wavelengths while reflecting green light, which is why most plants appear green. The absorbed light energy is then used to convert carbon dioxide and water into glucose and oxygen. This process is essential for plant growth and serves as the foundation for the energy supply in most ecosystems, as plants are primary producers.

The other options relate to different aspects of plant biology. For instance, while plants do store energy, this function is more accurately attributed to glucose, starch, and other compounds rather than chlorophyll itself. Water regulation and mineral absorption are also crucial functions in plants but are carried out through other systems and structures, such as roots and specialized tissues, rather than through chlorophyll.