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: Pharmacology
[{'content': 'Propranolol is contraindicated in diabetes mellitus because it: \nSelect and explain. \nA. Causes hyperglycemia, B. Causes seizures, C. Masks the hypoglycemic symptoms, D. Causes hypotension', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]