Which pairing is not correct?

Options

A. Vitamin D - Rickets
B. Vitamin K - Sterility
C. Thiamine - Beri-beri
D. Niacin - Pellagra

Answer

To determine which pairing is not correct, we need to analyze each of the given pairings:

1. **Vitamin D - Rickets**:
- Vitamin D is essential for calcium absorption in the body. A deficiency in Vitamin D leads to Rickets, a condition characterized by weak or soft bones in children. This pairing is correct.

2. **Vitamin K - Sterility**:
- Vitamin K is primarily involved in blood clotting. Its deficiency does not cause sterility; rather, it can lead to bleeding disorders, particularly in newborns (known as hemorrhagic disease of the newborn). This pairing is not correct.

3. **Thiamine (Vitamin B1) - Beriberi**:
- Thiamine is crucial for carbohydrate metabolism. A deficiency in Thiamine leads to Beriberi, which affects the cardiovascular and nervous systems. This pairing is correct.

4. **Niacin (Vitamin B3) - Pellagra**:
- Niacin is important for energy metabolism and a deficiency leads to Pellagra, characterized by dermatitis, diarrhea, and dementia. This pairing is also correct.

Based on the analysis, the pairing that is not correct is:

**Vitamin K - Sterility**.

### Summary of the Solution:
- Vitamin D causes Rickets (correct).
- Vitamin K does not cause sterility; it is associated with bleeding (not correct).
- Thiamine deficiency leads to Beriberi (correct).
- Niacin deficiency leads to Pellagra (correct).

### Final Answer:
The incorrect pairing is **Vitamin K - Sterility**.