Assertion (A): `CH_(3) CI` is obtained from `CH_(4)` by the action of `Cl_(2)`, in the presence of sunlight.
Reason (R): It is obtained by addition reaction.

Options

A. Both A and R are true and R is the correct explanation of A.
B. Both A and R are true but R is NOT the correct explanation of A.
C. A is true but R is false.
D. A is false and R is true.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Assertion:**
- The assertion states that `CH₃Cl` (methyl chloride) is obtained from `CH₄` (methane) by the action of `Cl₂` (chlorine) in the presence of sunlight.
- This is true because when methane reacts with chlorine in the presence of sunlight, a substitution reaction occurs where one hydrogen atom in methane is replaced by a chlorine atom, resulting in the formation of methyl chloride.

2. **Understanding the Reason:**
- The reason states that `CH₃Cl` is obtained by an addition reaction.
- This statement is false. The reaction between methane and chlorine is not an addition reaction; it is a substitution reaction. In an addition reaction, elements are added to a compound, typically involving double or triple bonds, which is not the case here.

3. **Conclusion:**
- Since the assertion is true and the reason is false, we conclude that the correct relationship is: A is true but R is false.

4. **Final Answer:**
- Therefore, the correct option is that Assertion (A) is true, and Reason (R) is false.

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