Exposure to ultraviolet light directly facilitates which of the following?: (A) Conversion of 7 dehydrocholesterol to 25-hydroxycholecalciferol, (B) Conversion of 25-hydroxycholecalciferol to 1,25- dihydroxycholecalciferol, (C) Transpo of calcium into the extracellular fluid, (D) Formation of calcium-binding protein
Answer is A. Ultraviolet light absorbed by the skin directly facilitates conversion of cholesterol to 25-hydroxycholecalciferol.