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: Pediatrics
[{'content': 'A 10 year old boy presents with mucosal bleeding of 1 week duration. The investigation of choice that will be most useful in him is – \nSelect and explain. \nA. Prothrombin time, B. Clotting time, C. Partial thromboplastin time, D. Platelet count', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Bleeding from mucosal surface suggests thrombocytopenia or defect in platelet function.\nFirst do platelet count, if there is thrombocytopenia, further investigation will be required.', 'role': 'assistant'}]