Cellular respiration is balanced by photosynthesis; the two processes work
together to maintain the cycling of carbon and oxygen among Earth systems.
What describes the roles of carbon dioxide and water in these two processes?
a. Carbon dioxide and water are the reactants of both processes.
b. Carbon dioxide and water are the products of both processes.
c. Carbon dioxide is a reactant of photosynthesis; water is a reactant of cellular
respiration.
d. Carbon dioxide and water are the reactants of photosynthesis and the
products of cellular respiration.