Assertion : Diamond glitters brilliantly.
Reason : Diamond does not absorb sunlight.

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 "Diamond glitters brilliantly." This is a well-known property of diamonds. They are prized for their brilliance and sparkle.

**Hint**: Consider what makes diamonds visually appealing and how they interact with light.

2. **Understanding the Reason**:
- The reason given is "Diamond does not absorb sunlight." This statement is also true; diamonds do not absorb visible light in a way that would diminish their brightness. Instead, they reflect and refract light.

**Hint**: Think about how materials interact with light—do they absorb it, reflect it, or transmit it?

3. **Analyzing the Relationship**:
- While both statements are true, we need to determine if the reason explains the assertion. The brilliance of diamonds is primarily due to the phenomenon of total internal reflection, which causes light to reflect multiple times within the diamond before it exits, contributing to its sparkle. The fact that diamonds do not absorb sunlight allows for this light to be reflected instead.

**Hint**: Reflect on whether the reason provided directly clarifies why the assertion is true.

4. **Conclusion**:
- Since both the assertion and the reason are true, but the reason does not adequately explain why diamonds glitter brilliantly (the explanation lies more in total internal reflection rather than absorption), we conclude that the assertion is correct, the reason is correct, but the reason does not explain the assertion.

5. **Final Answer**:
- The correct option is that both the assertion and reason are true, but the reason does not explain the assertion.

### Summary:
- Assertion: True (Diamonds do glitter brilliantly).
- Reason: True (Diamonds do not absorb sunlight).
- Relationship: The reason does not explain the assertion.