Which of the following is a protein deficiency disease?

Options

A. Osteomalacia
B. Kwashiorkor
C. Pellagra
D. Rickets

Answer

To determine which of the following is a protein deficiency disease, we need to analyze each option provided:

1. **Osteomalacia**: This is a condition characterized by the softening of bones due to a deficiency of vitamin D, calcium, or phosphate. It is not primarily related to protein deficiency.

2. **Kwashiorkor**: This is a severe form of malnutrition caused by inadequate protein intake, particularly in children. It is classified as Protein-Energy Malnutrition (PEM). Symptoms include swelling of the legs, stunted growth, and changes in hair color.

3. **Pellagra**: This disease is caused by a deficiency of niacin (vitamin B3) and is characterized by dermatitis, diarrhea, and dementia. It is not related to protein deficiency.

4. **Rickets**: This condition is due to a deficiency of vitamin D, calcium, or phosphate, leading to soft and weak bones in children. It is not a protein deficiency disease.

Based on the analysis, the correct answer is **Kwashiorkor**, as it is specifically associated with protein deficiency.

### Step-by-step Solution:
1. **Identify the diseases listed**: Osteomalacia, Kwashiorkor, Pellagra, Rickets.
2. **Analyze each disease**:
- Osteomalacia: Related to vitamin D/calcium deficiency.
- Kwashiorkor: Caused by protein deficiency (PEM).
- Pellagra: Caused by niacin deficiency.
- Rickets: Related to vitamin D/calcium deficiency.
3. **Determine which disease is a protein deficiency**: Kwashiorkor is the only disease that fits this criterion.
4. **Conclude the answer**: The protein deficiency disease is Kwashiorkor.