Calciferol or ergocalciferol.
The correct option is A Calciferol or ergocalciferol.
Vitamin $$D$$ is called calciferol or ergocalciferol. lt is a steroid hormone that has long been known for its important role in regulating body levels of calcium and phosphorus, and in mineralization of bone.
Vitamin $$D$$ in human body exist in two form :
(I) Vitamin $$D_2$$, also called as ergocalciferol.
(II) Vitamin $$D_3$$, also called as calciferol or cholecalciferol.