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: Pathology
[{'content': 'Most common lung cancer associated with ectopic ACTH is \nSelect and explain. \nA. Small cell cancer, B. Carcinoid, C. Squamous cell carcinoma, D. Adenocarcinoma', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ectopic ACTH production is most commonly associated with lung carcinoid.', 'role': 'assistant'}]