The correct option is C Calciferol
Vitamin D from the diet or dermal synthesis from sunlight is biologically inactive, activation requires enzymatic conversion (hydroxylation) in the liver and kidney. The chemical name for Vitamin D is calciferol. In humans, the most important compounds in this group are vitamin D3 (also known as cholecalciferol) and vitamin D2 (ergocalciferol). Cholecalciferol and ergocalciferol can be ingested from the diet and from supplements. Very few foods contain vitamin D, synthesis of vitamin D in the skin is the major natural sources of the vitamin. Dermal synthesis of vitamin D from cholesterol is dependent on sun exposure.