The reagents and conditions to convert methyl iodide to methane are

Options

A. Action of dry `Ag_(2)O`
B. KCN followed by refluxing with dil. HCL
C. aqueous NaOH followed by boiling `Al_(2)O_(3)` at 640K
D. Mg in dry ether followed by boiling with water

Explanation

To convert methyl iodide (CH3I) to methane (CH4), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Starting Material**:
- The starting material is methyl iodide (CH3I).

2. **Use of Grignard Reagent**:
- To convert methyl iodide to methane, we first need to create a Grignard reagent. This is done by reacting methyl iodide with magnesium (Mg) in dry ether.
- The reaction can be represented as:
\[ \text{CH}_3\text{I} + \text{Mg} \rightarrow \text{CH}_3\text{MgI} \]
- Here, CH3MgI is the Grignard reagent formed.

3. **Hydrolysis of Grignard Reagent**:
- The next step involves hydrolyzing the Grignard reagent. This is done by adding the Grignard reagent to boiling water (H2O).
- The reaction can be represented as:
\[ \text{CH}_3\text{MgI} + \text{H}_2\text{O} \rightarrow \text{CH}_4 + \text{Mg(OH)I} \]
- In this step, methane (CH4) is produced along with magnesium hydroxide iodide as a by-product.

4. **Final Product**:
- The final product of the reaction is methane (CH4), which is what we aimed to produce from methyl iodide.

### Conclusion:
Thus, the reagents and conditions to convert methyl iodide to methane are:
- **Reagents**: Magnesium (Mg) in dry ether followed by boiling water (H2O).

### Answer:
The correct option is **4: Mg in dry ether followed by boiling with water**.

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