Which one of the following pairs is NOT correctly matched?

1. A

   Vitamin-A - Orange

   Vitamin A is not characteristically paired with orange in this list. Oranges are the everyday source of vitamin C (ascorbic acid); vitamin A (retinol/beta-carotene) is classically tied to carrots, liver, papaya and dark greens. This incorrect pair is the official key.

2. B

   Vitamin-C - Lemon

   Vitamin C–lemon is correctly matched: citrus fruits are rich in ascorbic acid.

3. C

   Vitamin-D - Cod liver oil

   Vitamin D–cod liver oil is correctly matched: fish-liver oils are classic dietary sources of vitamin D.

4. D

   Vitamin-B - Rice bran

   Vitamin B–rice bran is correctly matched in the thiamine (B1) sense: bran is a traditional source, and polished-rice beriberi is the linked deficiency story.

Summary. Official key is (a) Vitamin A–orange, the unmatched pair. Citrus is the C-food in school tables; A is the night-blindness vitamin from animal liver and coloured vegetables. Lemon–C, cod liver oil–D and rice bran–B stay correctly matched. Honour the stored letter (a).