This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Urology, Subject name: Surgery
[{'content': 'All are seen in carcinoid syndrome \nSelect and explain. \nA. Diarrhoea, B. Constipation, C. Liver metastasis, D. 5-HT secretion', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Carcinoid syndrome is a paraneoplastic syndrome comprising the signs and symptoms that occur secondary to carcinoid tumors. The syndrome includes flushing and diarrhea, and less frequently, hea failure, vomiting and bronchoconstriction. It is caused by endogenous secretion of mainly serotonin and kallikrein. Ref: Internet sources', 'role': 'assistant'}]