The correct answer is B. photosynthesis and cellular respiration.
Chloroplasts are involved in photosynthesis, which converts light energy into chemical energy in the form of glucose. Mitochondria are responsible for cellular respiration, where glucose is broken down to produce ATP, the energy currency of the cell. These two processes are interconnected, as the products of photosynthesis (glucose and oxygen) are used in cellular respiration, and the products of cellular respiration (carbon dioxide and water) are used in photosynthesis, requiring interaction between chloroplasts and mitochondria.