This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology, Subject name: Pathology
Most common thyroid Cancer is 
Select and explain. 
A. Papillary carcinoma, B. Follicular carcinoma, C. Medullary carcinoma, D. Anaplastic carcinoma
A: Papillary carcinoma
Answer: A: Papillary carcinoma 
Explanation: Papillary carcinoma of thyroid: - constitutes >85% of all thyroid carcinoma - occurs due to mutation of genes encoding: *RET gene *NTRK1 receptor tyrosine kinases *BRAF gene These tumours may be solitary or multivocal. On microscopy: - branching papillae with fibrovascular stalk lined by cuboidal epithelium - nuclei of cells are optically clear with dispersed chromatin and has Orphan Annie eye nuclei (Ref : ROBBINS Text book of pathology) REF IMG