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': 'Flexion of metacarpophalangeal joint is produced by all except \nSelect and explain. \nA. Lumbricals, B. Dorsal interossei, C. Palmar interossei, D. Extensor pollicus longus', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Flexion of metacarpophalangeal joint is by lumbricals and both palmar and dorsal interossei. Abduction is by the action of dorsal interossei. Adduction is by the actions of palmar interossei . B D Chaurasia 7th edition Page no: 163', 'role': 'assistant'}]