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: Orthopaedics
[{'content': 'A cricketer holds a catch and then presents with pain at the base of the right thumb. He should be examined to specifically rule out damage to which of the following structure : \nSelect and explain. \nA. Extensor pollicis brevis, B. Abductor pollicis longus, C. Volar plate, D. Ulnar collateral ligament', 'role': 'user'}, {'content': "Answer: D \nExplanation: This is a case of skier's thumb i.e. acute injury to ulnar collateral ligament which occurs when there is abrupt abduction of the thumb. Injury is common in ball handling athletes.\nPatient presents with pain, tenderness and swelling at the base of thumb.", 'role': 'assistant'}]