Which of the Following is the Active Form of Calcitriol

Question

Which of the following is the active form of calcitriol?
A) calcium
B) vitamin A
C) vitamin C
D) vitamin D
E) sodium

Accepted Answer

Calcitriol is the active form of vitamin D, which is synthesized in the kidneys. Calcium is a mineral and not a form of vitamin D, while vitamin A and C are not related to calcitriol synthesis. Sodium is an electrolyte and not involved in vitamin D metabolism.