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: Social & Preventive Medicine
[{'content': 'Which is true of typhoid? \nSelect and explain. \nA. Male carriers though less are more dangerous, B. Female carriers are less common, C. Gall bladder usually not involved in carrier state, D. Tetracycline is the DOC for carriers', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]