খ) Parafollicular cells are smaller than follicular cells
গ
গ) Each follicle consists of a simple epithelium and a central lumen
ঘ
ঘ) Parafollicular cells produce parathormone
ব্যাখ্যা
-Follicular cells are columnar when stimulated -Parafollicular cells are larger than follicular cells -Parafollicular cells produce calcitonin, follicular cells produce T3,T4.