State the reason, why GaAs is most commonly used in making of a solar cell.

Explanation

**Step-by-Step Solution:**

1. **Understanding Solar Cells**: Solar cells convert sunlight into electricity. They are made from semiconductor materials that can absorb light and generate charge carriers (electrons and holes).

2. **Material Selection**: The choice of material for solar cells is crucial for their efficiency. Different materials have different properties that affect how well they can absorb sunlight and convert it into electrical energy.

3. **Gallium Arsenide (GaAs)**: GaAs is a semiconductor material that is commonly used in solar cells.

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