Noise is

Options

A. Loud sound
B. Unwanted sound
C. Constant sound
D. Sound of high frequency.

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks for the definition of noise. We need to identify which option best describes noise.

2. **Analyzing the Options**:
- **Loud Sound**: While noise can be loud, not all loud sounds are considered noise.
- **Unwanted Sound**: This is a key characteristic of noise. Noise is typically defined as sound that is unpleasant or disruptive.
- **Constant Sound**: Noise may be constant, but this is not a defining characteristic of noise.
- **Sound of High Frequency**: Noise can include high-frequency sounds, but again, this is not a defining feature.

3. **Defining Noise**: From the analysis, noise is best defined as "unwanted sound." It is sound that is judged to be unpleasant or disruptive to hear, regardless of its loudness or frequency.

4. **Conclusion**: Based on the definitions and characteristics discussed, the correct answer to the question "Noise is" is **unwanted sound**.