What Is a Feature of Vitamin D

What is a feature of vitamin D?

A) The bioavailability of vitamin D from soy milk is low.
B) Lifeguards on southern beaches have increased risk for vitamin D toxicity.
C) Only about one-half of the world's population relies on sunlight to maintain adequate vitamin D nutrition.
D) Prolonged exposure to sunlight degrades the vitamin D precursor in skin, thus preventing vitamin D toxicity.