Assertion : Pantothenic acid deficiency is probably the most common vitamin deficiency.
Reason: Macrocytic characteristic feature of pantothenic acid deficiency.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion
B. If both assertion and reason are true but reason is not the correct explanation of assertion
C. If assertion is true but reason is false
D. If both assertion and reason are false.

Explanation

To solve the question, we need to analyze both the assertion and the reason provided.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Pantothenic acid deficiency is probably the most common vitamin deficiency."
- Pantothenic acid is also known as Vitamin B5. It is involved in various metabolic processes, including the metabolism of carbohydrates, fats, and proteins.

2. **Evaluating the Assertion**:
- Despite its importance, pantothenic acid deficiency is not commonly reported in humans. This is because it is widely available in many foods such as cereals, eggs, and legumes.
- Therefore, the assertion that it is the most common vitamin deficiency is incorrect.

3. **Understanding the Reason**:
- The reason states that "Macrocytic characteristic feature of pantothenic acid deficiency."
- Macrocytic anemia is typically associated with deficiencies in folic acid (Vitamin B9) and Vitamin B12, not pantothenic acid.

4. **Evaluating the Reason**:
- Since pantothenic acid deficiency does not lead to macrocytic anemia, the reason provided is also incorrect.

5. **Conclusion**:
- Both the assertion and the reason are false. Hence, the correct answer is that both the assertion and reason are false.

### Final Answer:
Both assertion and reason are false.

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