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: Gynaecology & Obstetrics
[{'content': "Drug of choice in thyrotoxicosis in pregnancy is : \nSelect and explain. \nA. Carbimazole, B. Lugol's iodine, C. Propranolol, D. Radioactive iodine", 'role': 'user'}, {'content': 'Answer: A \nExplanation: Carbimazole', 'role': 'assistant'}]