Which one of the following pairs is not correctly matched?

Options

A. `Vitamin B_(12)` - Pernicious anemia
B. Vitamin `B_(6)` - Loss of appetite
C. Vitamin `B_(1)` - Beri - beri
D. Vitamin `B_(2)` - Pellagra

Answer

To determine which pair is not correctly matched, we will analyze each vitamin and its corresponding disease or condition:

1. **Vitamin B12 (Cobalamin)** - This vitamin is known to cause pernicious anemia when deficient. This match is **correct**.

2. **Vitamin B6 (Pyridoxine)** - A deficiency in vitamin B6 can lead to symptoms such as loss of appetite. This match is also **correct**.

3. **Vitamin B1 (Thiamine)** - A deficiency in vitamin B1 is known to cause beriberi disease. This match is **correct**.

4. **Vitamin B2 (Riboflavin)** - The claim here is that vitamin B2 causes pellagra. However, pellagra is actually caused by a deficiency in vitamin B3 (Niacin), not vitamin B2. Therefore, this match is **incorrect**.

Based on the analysis, the pair that is not correctly matched is **Vitamin B2 with Pellagra**.

### Final Answer:
The pair that is not correctly matched is Vitamin B2 (Riboflavin) with Pellagra.

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