Thin limbs, oedema and diarrhoea develop due to protein deficiency in
(a) Marasmus
(b) Kwashiorkor
(c) Pellagra
(d) Megaloblastic anaemia

Options

A. Marasmus
B. Kwashiorkor
C. Pellagra
D. Megaloblastic anaemia

Answer

To solve the question regarding which condition is characterized by thin limbs, oedema, and diarrhoea due to protein deficiency, we can analyze the options step by step.

### Step-by-Step Solution:

1. **Understanding the Symptoms**: The symptoms mentioned in the question are thin limbs, oedema, and diarrhoea. We need to identify which condition corresponds to these symptoms specifically due to protein deficiency.

2. **Analyzing Option (a) Marasmus**:
- Marasmus is a form of severe malnutrition characterized by energy deficiency. It is known as protein-energy malnutrition (PEM).
- Symptoms include extreme thinness, prominent ribs, and stunted growth. However, it does not typically present with oedema or diarrhoea.
- **Conclusion**: Marasmus does not match all the symptoms.

3. **Analyzing Option (b) Kwashiorkor**:
- Kwashiorkor is specifically caused by protein deficiency, even when caloric intake may be adequate.
- It is characterized by symptoms such as thin limbs, retarded growth, oedema (swelling due to fluid retention), and often diarrhoea.
- **Conclusion**: Kwashiorkor matches all the symptoms listed in the question.

4. **Analyzing Option (c) Pellagra**:
- Pellagra is caused by a deficiency of niacin (vitamin B3), not protein.
- Symptoms include dermatitis, diarrhoea, and dementia, but it does not involve oedema or thin limbs.
- **Conclusion**: Pellagra is not related to protein deficiency.

5. **Analyzing Option (d) Megaloblastic Anaemia**:
- This condition is characterized by the presence of large, abnormal red blood cells due to deficiencies in vitamin B12 or folate.
- It does not relate to protein deficiency and does not present with the symptoms listed.
- **Conclusion**: Megaloblastic anaemia is not related to protein deficiency.

### Final Answer:
Based on the analysis, the correct answer is **(b) Kwashiorkor**.

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