<prompt> Medullary thyroid carcinoma is associated with-MEN IMEN IIMEN IVAll of the above  <response>: Ans. is b i.e., MEN II o About 70 of tumors arise sporadically. The remainder occurs in the rsetting of MEN syndrome 2A or 2B or as familial tumors without an associated MEN syndrome familial medullary thyroid carcinoma, or FMTC 