The process of photosynthesis involves both physical and chemical changes, and the first choice highlights this dual aspect effectively. During photosynthesis, leaves grow in size, which is a physical change. This growth results from the plant's absorption of water and nutrients, leading to an increase in leaf area and volume without altering the chemical composition of the leaf itself.
At the same time, the process fundamentally involves a chemical change: atoms rearrange to form glucose and oxygen from carbon dioxide and water, using sunlight as an energy source. This transformation of substances demonstrates the chemical aspect of photosynthesis, showcasing how the constituents undergo a change at the atomic level to create new compounds. Thus, this option successfully captures the essence of how photosynthesis embodies both physical growth and significant chemical reactions.
Other choices might misrepresent the nature of physical and chemical changes in photosynthesis or focus on aspects that do not align strictly with the scientific definitions of these processes.