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: Surgery
What percentage of cold thyroid nodules are malignant? 
Select and explain. 
A. 70-80%, B. 50-60%, C. 40-50%, D. 10-20%
D: 10-20%
Answer: D: 10-20% 
Explanation: Cold nodules (don’t take up radioactive iodine) are more likely to be malignant (15-20%) than hot (take up radioactive iodine) nodules (1-3%).