Assertion : `CH_2=CH-CH_2-X` is an examples of allyl halides.
Reason: These are the compounds in which the halogen atom is called to an `sp^2` hybridised carbon atom.

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 assetion 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 `CH2=CH-CH2-X` is an example of allyl halides.
- Allyl halides are compounds where a halogen atom is attached to the carbon atom adjacent to a carbon-carbon double bond.

2. **Analyzing the Structure**:
- The structure `CH2=CH-CH2-X` can be broken down:
- The first carbon (C1) is part of the double bond (C=C).
- The second carbon (C2) is also part of the double bond.
- The third carbon (C3) is connected to the halogen (X).
- Here, C1 and C2 are sp2 hybridized due to the presence of a double bond, while C3 is sp3 hybridized.

3. **Understanding the Reason**:
- The reason states that the halogen atom is attached to an sp2 hybridized carbon atom.
- In the structure `CH2=CH-CH2-X`, the halogen (X) is actually attached to C3, which is sp3 hybridized, not to C1 or C2 which are sp2 hybridized.

4. **Evaluating the Assertion and Reason**:
- The assertion is true because `CH2=CH-CH2-X` is indeed an allyl halide.
- The reason is false because the halogen is attached to an sp3 hybridized carbon (C3), not an sp2 hybridized carbon.

5. **Conclusion**:
- Therefore, the correct answer is that the assertion is true, but the reason is false.

### Final Answer:
- The assertion is true, but the reason is false.