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': 'Monitoring for Iodine levels is done by \nSelect and explain. \nA. Urinary excretion of Iodine, B. TSH, T3 and T4 levels, C. Iodine level in soil, D. All of the above', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]