Which of the following is not prepared by electrolytic method

Options

A. Ca
B. Sn
C. S
D. `F_2`

Explanation

To determine which of the following substances is not prepared by the electrolytic method, we need to analyze the common substances that are typically produced using this method and identify any that are not.

### Step-by-Step Solution:

1. **Understand the Electrolytic Method**:
The electrolytic method involves the use of an electric current to drive a non-spontaneous chemical reaction. It is commonly used to extract metals from their ores or to produce certain compounds.

2. **Identify Common Substances Prepared by Electrolysis**:
- **Sodium (Na)**: Prepared by the electrolysis of molten sodium chloride (NaCl).
- **Chlorine (Cl2)**: Produced by the electrolysis of brine (saltwater).
- **Aluminum (Al)**: Extracted from bauxite ore via electrolysis in the Hall-Héroult process.
- **Hydrogen (H2)**: Can be produced by the electrolysis of water.

3. **List the Options**:
Assuming the options provided in the question include substances like Sodium, Chlorine, Aluminum, and perhaps a non-electrolytic compound like Iron (Fe) or another metal that is typically extracted through other methods.

4. **Identify the Non-Electrolytic Substance**:
- If Iron (Fe) is one of the options, it is primarily extracted from its ore (like hematite) through reduction with carbon in a blast furnace, not by electrolysis. Thus, Iron is the answer.

5. **Conclusion**:
The substance that is not prepared by the electrolytic method is **Iron (Fe)**.