Riboflavin deficiency causes:

Options

A. scurvy
B. pellagra
C. beri-beri
D. cheilosis

Answer

### Step-by-Step Solution:

1. **Identify Riboflavin**: Riboflavin is also known as Vitamin B2. It is an essential nutrient that plays a key role in energy production and the metabolism of fats, drugs, and steroids.

2. **Understand the Deficiency Effects**: When there is a deficiency of riboflavin (Vitamin B2), it can lead to various health issues. One of the notable conditions caused by this deficiency is cheilosis.

3. **Define Cheilosis**: Cheilosis is characterized by the cracking or fissuring at the corners of the mouth and lips. It can lead to discomfort and may be accompanied by inflammation.

4. **Differentiate from Other Deficiencies**: It is important to note that other vitamin deficiencies cause different conditions:
- Vitamin B1 deficiency leads to beriberi.
- Vitamin C deficiency results in scurvy.
- Vitamin B6 deficiency is associated with pellagra.

5. **Conclude the Answer**: Therefore, the primary condition caused by riboflavin deficiency is cheilosis.

### Final Answer:
Riboflavin deficiency causes cheilosis, which is the cracking at the corners of the mouth and lips.

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