In the Citric Acid Cycle, Succinate Dehydrogenase Catalyzes the Conversion

In the citric acid cycle, succinate dehydrogenase catalyzes the conversion of succinate to fumarate. This reaction is inhibited by malonate, which resembles succinate but cannot be acted upon by succinate dehydrogenase. Which of the following statements best describes the role played by molecules described in the reaction?

A) Succinate dehydrogenase is the enzyme, and fumarate is the substrate in the reaction.
B) Succinate dehydrogenase is the enzyme, and malonate is the substrate in the reaction.
C) Succinate is the substrate, and fumarate is the product in the reaction.
D) Fumarate is the product, and malonate is a noncompetitive inhibitor in the reaction.