A transverse wave consists of

Options

A. only crests
B. only troughs
C. both crests and troughs
D. rarefactions and compressions

Explanation

To solve the question "A transverse wave consists of:", we will analyze the characteristics of transverse waves step by step.

### Step-by-Step Solution:

1. **Understanding Transverse Waves**:
- Transverse waves are a type of wave where the particle displacement is perpendicular to the direction of wave propagation.

2. **Identifying Wave Components**:
- In a transverse wave, there are two main components: crests and troughs.
- **Crests** are the highest points of the wave.
- **Troughs** are the lowest points of the wave.

3. **Visual Representation**:
- If we visualize a transverse wave, we can see alternating high points (crests) and low points (troughs) along the wave.

4. **Excluding Other Options**:
- The other options provided in the question are "only crests," "only troughs," and "rarefactions and compressions."
- Rarefactions and compressions are characteristics of longitudinal waves, not transverse waves.

5. **Conclusion**:
- Therefore, a transverse wave consists of both crests and troughs.

### Final Answer:
The correct answer is: **both crests and troughs**.

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