This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Thyroid Gland, Subject name: Surgery
Prophylactic thyroidectomy is done for: 
Select and explain. 
A. Hashimoto, B. MEN 2B syndrome, C. Reidel, D. Graves
B: MEN 2B syndrome
Answer: B: MEN 2B syndrome 
Explanation: Ans. (b)MEN 2BRef: Schwartz 10th edition Page 1550* Patients with RET oncogene mutations, MEN- 2a Syndrome must be taken for Prophylactic thyroidectomy at 5 years* MEN- 2b Syndrome must be taken for Surgery at 1 year