Which of the following insects is useful to man?

Options

A. Dragon fly
B. Grass hopper
C. Moth
D. Termite

Answer

To solve the question "Which of the following insects is useful to man?" we need to analyze the options provided:

1. **Dragonfly**
2. **Grasshopper**
3. **Moth**
4. **Termite**

### Step-by-Step Solution:

**Step 1: Understand the role of each insect.**
- **Dragonfly**: Known for their predatory behavior, dragonflies primarily feed on mosquitoes and their larvae. This helps control mosquito populations, which are vectors for various diseases.
- **Grasshopper**: Generally considered pests in agriculture as they can cause significant damage to crops.
- **Moth**: While some moths can be beneficial (like those that pollinate), many are also pests that can damage clothing and stored products.
- **Termite**: Often viewed as pests because they can damage wooden structures and crops.

**Step 2: Identify the beneficial insect.**
- Among the options, the dragonfly stands out as it actively helps in reducing the population of mosquitoes, thus protecting humans from diseases like malaria and dengue.

**Step 3: Conclude the answer.**
- Based on the analysis, the insect that is most useful to man is the **dragonfly**.

### Final Answer:
**Option A: Dragonfly**

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