In the life cycle of common round worm 2nd and 3rd moults occur in

Options

A. In the moist soil
B. Intestine of man
C. In the alveoli of lungs
D. In the liver

Answer

### Step-by-Step Solution:

1. **Understanding the Life Cycle of Common Round Worm**:
- The common round worm, scientifically known as Ascaris, has a complex life cycle that includes several stages of development.

2. **Identifying the Stages of Moulting**:
- In the life cycle of Ascaris, the larvae undergo a series of moults (also known as molts). Moulting is a process where the organism sheds its outer layer to grow.

3. **First Moulting**:
- The first moult occurs in the soil when the larvae develop from the shelled eggs. This is the initial stage of development.

4. **Second and Third Moulting**:
- The second and third moults occur in a specific location within the host. According to the information, these moults take place in the **alveoli of the lungs**.

5. **Final Moulting**:
- The final moult occurs in the intestine of the host, where the larvae mature into adult worms.

6. **Conclusion**:
- Based on the information gathered, the second and third moults of the common round worm occur in the alveoli of the lungs.

### Answer:
The second and third moults of the common round worm occur in the **alveoli of the lungs**.

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