The following reaction is known as:
`C_(6)H_(6)+CH_(3)Cl overset(AlCl_(3)) underset(("Anhy")) to C_(6)H_(5)CH_(3)+HCl`

Options

A. Wurtz - Fittig's reaction
B. Friedal - Craft's reaction
C. Rosenmund reaction
D. Sandmeyer reaction

Explanation

To determine the name of the reaction given by the equation:

\[ C_6H_6 + CH_3Cl \overset{(AlCl_3)}{\rightarrow} C_6H_5CH_3 + HCl \]

we can analyze the components and the process involved.

### Step-by-Step Solution:

1. **Identify the Reactants**:
- The reactants are benzene (\(C_6H_6\)) and methyl chloride (\(CH_3Cl\)).
- Benzene is an aromatic hydrocarbon, and methyl chloride is an alkyl halide.

**Hint**: Look for the types of compounds involved in the reaction.

2. **Identify the Catalyst**:
- The reaction uses anhydrous aluminum chloride (\(AlCl_3\)) as a catalyst.
- This catalyst is commonly used in electrophilic aromatic substitution reactions.

**Hint**: Recognize the role of the catalyst in facilitating the reaction.

3. **Understand the Reaction Mechanism**:
- In this reaction, the methyl group from methyl chloride replaces one hydrogen atom on the benzene ring.
- This is a typical characteristic of alkylation reactions where an alkyl group is introduced to an aromatic compound.

**Hint**: Consider what happens to the benzene ring during the reaction.

4. **Identify the Product**:
- The product formed is toluene (\(C_6H_5CH_3\)) and hydrochloric acid (\(HCl\)).
- The formation of toluene indicates that an alkyl group has been added to the benzene.

**Hint**: Look at the products to confirm the type of reaction taking place.

5. **Name the Reaction**:
- This reaction is known as **Friedel-Crafts Alkylation**.
- It is a specific type of Friedel-Crafts reaction where an alkyl group is introduced to an aromatic ring.

**Hint**: Recall the name of the reaction that involves the alkylation of aromatic compounds.

### Final Answer:
The following reaction is known as **Friedel-Crafts Alkylation**.