Answer
b.7-dehydrocholesterol
Work Step by Step
Epidermal keratinocytes use ultraviolet radiation from sunlight to convert 7-dehydrocholesterol to previtamin D.The warmth of sunlight on the skin converts this to vitamin D.
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.