This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Upper limb, Subject name: Anatomy
[{'content': 'The muscle of hand that contains a sesamoid bone is \nSelect and explain. \nA. Flexor pollicis brevis, B. Flexor pollicis longus, C. Opponens pollicis, D. Adductor pollicis', 'role': 'user'}, {'content': 'Answer: D \nExplanation: The tendon of inseion of adductor pollicis on the medial side of base of proximal phalanx of thumb contains a sesamoid bone.Reference: Textbook of anatomy, Upper limb, and thorax, Vishram Singh, 2nd edition, page no.144', 'role': 'assistant'}]