This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Biochemistry
[{'content': 'Which of the following statement regarding Nitric Oxide Synthase is TRUE? \nSelect and explain. \nA. It is inhibited by Calcium, B. It accepts electrons from NADH, C. It catalyzes a dioxygenase reaction, D. It requires NADPH, FAD, FMN and Heme iron', 'role': 'user'}, {'content': "Answer: D \nExplanation: Nitric oxide synthase is an enzyme required for the synthesis of nitric oxide from arginine. It is a dimeric protein and contains heme, FAD, FMN, tetrahydrobiopterin and calmodulin. This enzyme utilises molecular oxygen and NADPH. Ref: Harper's Illustrated Biochemistry, 26th Edition, Page 572; Lippincott's Biochemistry, 2nd Edition, Page 85; Textbook of Biochemistry By D M Vasudevan, 3rd Edition, Page 178", 'role': 'assistant'}]