Assertion: One can see bright orange coloured band of DNA in a ethidium bromide stained gel exposed to infra-red light
Reason :One cannot see pure DNA fragments in the visible & UV light & without staining

Options

A. If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion
B. It both Assertion & Reason are True but Reason is not a correct explanation of the Assetion
C. If Assertion is True but the Reason is False
D. If both Assertion & Reason are false

Answer

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

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states: "One can see bright orange colored band of DNA in an ethidium bromide stained gel exposed to infrared light."
- Ethidium bromide is a fluorescent dye used to stain DNA. When exposed to UV light, it emits a bright orange color, allowing visualization of DNA bands. However, it does not emit this color under infrared light.

**Conclusion**: The assertion is **false** because the DNA bands are visible under UV light, not infrared light.

2. **Understanding the Reason**:
- The reason states: "One cannot see pure DNA fragments in the visible & UV light without staining."
- Pure DNA fragments are indeed not visible to the naked eye without staining. However, when stained with ethidium bromide, they can be visualized under UV light.

**Conclusion**: The reason is **false** because while it is true that pure DNA is not visible without staining, the statement implies that it cannot be seen at all under UV light, which is incorrect.

3. **Final Evaluation**:
- Since both the assertion and the reason are false, the correct answer is that both the assertion and reason are false.

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

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