The material used in solar cells contains

Options

A. `Cs`
B. `Si`
C. `Sn`
D. `Ti`

Explanation

To solve the question regarding the material used in solar cells, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Classification of Solar Cells**:
- Solar cells can be classified into three generations: 1st generation, 2nd generation, and 3rd generation.

2. **Identify the 1st Generation Solar Cells**:
- The 1st generation solar cells are known as conventional, traditional, or wafer-based cells.

3. **Determine the Material Composition**:
- The primary materials used in 1st generation solar cells are crystalline silicon. This includes two types:
- **Monocrystalline Silicon**: Made from a single crystal structure.
- **Polysilicon**: Made from multiple crystal structures.

4. **Conclude the Answer**:
- Based on the information, the material predominantly used in solar cells, especially the 1st generation, is silicon.

### Final Answer:
The material used in solar cells contains silicon.

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