The Clemmensen reduction of ketones is carried out in the presence of

Options

A. `Zn-Hg` with HCl
B. `LIAIH_(4)`
C. `H_2 and Pt` as catalyst
D. Glycol with KOH

Explanation

To solve the question regarding the Clemmensen reduction of ketones, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Clemmensen Reduction**: The Clemmensen reduction is a chemical reaction that reduces ketones (and aldehydes) to alkanes. This process is particularly useful in organic chemistry for converting carbonyl compounds into hydrocarbons.

2. **Identify the Reagents Used**: The Clemmensen reduction specifically utilizes zinc amalgam (a mixture of zinc and mercury) and hydrochloric acid (HCl) as the reducing agent.

3. **Reaction Mechanism**: In this reduction, the carbonyl group (C=O) of the ketone is reduced to a methylene group (C-H2) through the action of zinc amalgam in the presence of hydrochloric acid. The zinc serves as the reducing agent, while the mercury helps to stabilize the zinc.

4. **Evaluate the Options Given**: The options provided are:
- A) Zinc mercury with hydrochloric acid
- B) Lithium ammonium hydride
- C) Hydrogen and platinum as catalyst
- D) Glycerol with KOH

Among these, option A is the only one that correctly describes the reagents used in the Clemmensen reduction.

5. **Conclusion**: Therefore, the correct answer to the question is that the Clemmensen reduction of ketones is carried out in the presence of zinc mercury with hydrochloric acid.

### Final Answer:
The Clemmensen reduction of ketones is carried out in the presence of **zinc mercury with hydrochloric acid**.

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