Which of the following groups is classically recommended to receive a specific vitamin (or its supplement) because of increased physiological need or dietary restriction?

• A. Young adult omnivores with balanced diets are routinely recommended to take high-dose vitamin A supplements to prevent common colds and increase athletic performance.
• B. Individuals who consume a varied diet including animal products and dairy are universally required to take vitamin B12 injections to avoid deficiency.
• C. Pregnant women are advised to take folic acid (B9) supplements to reduce the risk of neural tube defects in the developing fetus.
• D. All teenagers should avoid prenatal vitamins because vitamins are unnecessary until middle age.

Answer: (C)