Clouds are

Options

A. tiny drops of water floating in air.
B. mixture of dust and water vapour.
C. particles of water vapour.
D. rain drops in air.

Explanation

**Step-by-Step Solution:**

1. **Understanding Clouds**:
- Clouds are formed when water vapor in the atmosphere cools and condenses into tiny droplets or ice crystals.

2. **Composition of Clouds**:
- Clouds consist of a large collection of very tiny droplets of water or ice crystals. These droplets are extremely small and light.

3. **Floating in the Air**:
- The tiny size and lightness of these droplets allow them to float in the air, forming visible clouds.

4. **Conclusion**:
- Therefore, the correct treatment of clouds is that they are a large collection of very tiny droplets of water or ice crystals that float in the air.

**Final Answer**: Clouds are a large collection of very tiny droplets of water or ice crystals that float in the air.

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