Question

Which of the following is a water-soluble vitamin?

• A. Folic Acid
• B. Vitamin A
• C. Vitamin K
• D. Linolenic Acid

Hint:

Use the acronym ADEK to remember the fat-soluble vitamins: Vitamins A, D, E, and K. All other essential vitamins (Vitamin C and B-complex vitamins, like Folic acid) are water-soluble.

Answer 1

The Correct Option is A

Step 1: Understanding the Question:
The question asks to identify which of the listed substances is classified as a water-soluble vitamin.

Step 2: Detailed Explanation:

• Vitamin Classification: Vitamins are essential organic micronutrients classified into two primary categories based on their solubility:

• Water-Soluble Vitamins: These include Vitamin C (ascorbic acid) and all the B-complex vitamins. They dissolve in water, are not stored in significant amounts in the body (excess is excreted in urine), and must be consumed regularly.

• Fat-Soluble Vitamins: These include Vitamins A, D, E, and K. They are soluble in organic lipids, absorbed along with dietary fats, and stored in the liver and adipose tissues.

• Analyzing the Options:

• Folic Acid (Vitamin $B_9$): A member of the water-soluble B-complex vitamins, critical for DNA synthesis, cell division, and red blood cell maturation. This matches option (A).

• Vitamin A (Retinol): A fat-soluble vitamin critical for vision and immune function, corresponding to option (B).

• Vitamin K (Phylloquinone/Menaquinone): A fat-soluble vitamin essential for blood coagulation, corresponding to option (C).

• Linolenic Acid: This is an essential fatty acid ($\omega$-3 polyunsaturated fat), not a vitamin, corresponding to option (D).

Step 3: Final Answer:
Folic acid is a B-complex vitamin and is water-soluble, making option (A) the correct choice.