<prompt> A 20 year old male presents with chronic constipation, head ache and habitus, neuromas of tongue, medullated corneal nerve fibers and nodule of 22 cm size in left lobe of thyroid. This patient is a case of:Sporadic medullary carcinoma of thyroidFamilial medullary carcinoma of thyroidMEN-2AMEN-2B  <response>: MEN-2A Sipple Syndrome MEN MEN-2B MEN-3 Components Medullary carcinoma thyroid Pheochromocytoma Parathyroid hyperplasia or adenoma Hirschprung;s Disease Cutaneous lichen amyloidosis Medullary carcinoma thyroid Pheochromocytoma Intestinal ganglioneuromas Mucosal neuromas Megacolon Marfanoid features Defect RET oncogenic Cysteine codon Chromosome: 10 RET oncogene tyrosine kinase domain Chromosome: 10 Transmission Autosomal dominant Autosomal Dominant Ref: Sabiston 20th edition Pgno: 993,1003 