Which of the following produces noise only?

Options

A. Jet engine
B. Harmonium
C. Flute
D. Guitar

Explanation

To determine which of the following options produces noise only, we first need to understand the definition of noise.

### Step-by-Step Solution:

1. **Understanding Noise**:
- Noise is defined as an unpleasant or unwanted sound that is irritating to hear. It is subjective, meaning that what one person finds noisy, another may not.

2. **Analyzing the Options**:
- We need to evaluate each option given in the question to see if it produces noise or pleasant sounds.

3. **Evaluating Each Option**:
- **Jet Engine**: The sound produced by a jet engine is typically loud and can be perceived as irritating or unpleasant. Therefore, it falls under the category of noise.
- **Harmonium**: The harmonium produces melodious sounds that are generally pleasant to hear. Thus, it does not produce noise.
- **Flute**: The flute also produces melodious and soothing sounds, which are not considered noise.
- **Guitar**: A guitar can produce both pleasant music and, in some cases, loud sounds, but it is primarily associated with music rather than noise.

4. **Conclusion**:
- Among the options provided, the jet engine is the only one that produces noise only, as it is considered irritating and unpleasant to hear.

### Final Answer:
The sound of the jet engine produces noise only.

---