Piezoelectric crystals are used in

Options

A. TV
B. Radio
C. Record player
D. Freeze

Explanation

To solve the question about the applications of piezoelectric crystals, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Piezoelectric Crystals**:
- Piezoelectric crystals are materials that can generate an electric charge in response to applied mechanical stress. This property is known as the piezoelectric effect.

2. **Identifying Applications**:
- We need to evaluate the options provided:
1. TV
2. Radio
3. Record player
4. Freeze

3. **Analyzing Each Option**:
- **TV**: While modern TVs may use various electronic components, piezoelectric crystals are not specifically known for their use in TVs.
- **Radio**: Similar to TVs, radios use various electronic components, but piezoelectric crystals are not a primary component.
- **Record Player**: Piezoelectric crystals are commonly used in record players (turntables) to convert the mechanical vibrations from the record into electrical signals.
- **Freeze**: This option does not relate to the function of piezoelectric crystals.

4. **Conclusion**:
- Based on the analysis, the correct answer is option 3: Record player. Piezoelectric crystals are indeed used in record players to help convert sound vibrations into electrical signals.

### Final Answer:
Piezoelectric crystals are used in **Record players** (Option 3).