Deficiency that can lead to night blindness?

• A. Vitamin D
• B. Vitamin A
• C. Vitamin K
• D. Vitamin C

Answer: (B)

Night vision relies on a pigment in the rods of the retina called rhodopsin, which needs vitamin A to be produced in the form of retinal. When light hits rhodopsin, it breaks down and must be rebuilt so the eye can adapt to darkness again. If vitamin A intake is low, there isn’t enough retinal to replenish rhodopsin, so the eyes struggle to adjust from bright to dark settings, leading to night blindness.

Vitamin A is found in foods like liver, dairy, eggs, and colorful fruits and vegetables that provide beta-carotene, the body’s vitamin A precursor. The other vitamins listed don’t play a direct role in the visual cycle, so deficiency in them isn’t linked to night vision problems.