Which vitamin is fat-soluble?

• A. Vitamin B
• B. Vitamin H
• C. Vitamin D
• D. Vitamin C

Answer: (C)

Fat-soluble vitamins dissolve in fats and are stored in the body's fatty tissues and liver. They are absorbed in the small intestine along with dietary fats, using bile and fat for emulsification, and they travel in the body tied to proteins and lipids. Because they can be stored, the body can accumulate them if taken in excess, which is why they’re not needed every day. In contrast, water-soluble vitamins move into the bloodstream directly and are excreted in urine more readily, so they require more regular intake.

Among the options, the vitamin that fits the fat-soluble pattern is vitamin D. Vitamins B and C, and biotin (often referred to as vitamin H), are water-soluble. Therefore, vitamin D is the fat-soluble one.