Assertion :- G -cells of gastric gland secrete intrinsic castle's factor.
Reason:- This factor help in vitamin B2 absorption.

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.

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that G-cells of the gastric gland secrete intrinsic Castle's factor.
- **Evaluation**: This statement is false. G-cells actually secrete gastrin, which is a hormone that stimulates gastric motility and the secretion of hydrochloric acid (HCl).

2. **Understanding the Reason**:
- The reason provided is that this intrinsic factor helps in the absorption of vitamin B2.
- **Evaluation**: This statement is also false. The intrinsic factor is crucial for the absorption of vitamin B12, not vitamin B2. Vitamin B2 is absorbed through different mechanisms and does not require intrinsic factor.

3. **Conclusion**:
- Since both the assertion and reason are false, we can conclude that the correct answer is that both the assertion and reason are false.

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

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