Complete metamorphosis occurs in

Options

A. Housefly and Cockroach
B. Mosquito and Cockroach
C. Housefly and Mosquito
D. Cockroach and Locust.

Answer

**Step-by-Step Solution:**

1. **Understanding Metamorphosis**: Metamorphosis is the process by which insects undergo significant changes in their life cycle. There are two main types: complete metamorphosis and incomplete (or gradual) metamorphosis.

2. **Defining Complete Metamorphosis**: Complete metamorphosis involves four distinct life stages: egg, larva, pupa, and adult. Each stage is markedly different in form and function. The larva is often worm-like and primarily focused on feeding, while the adult has wings and is capable of reproduction.

3. **Identifying the Stages**:
- **Egg**: The initial stage where the insect begins its life.
- **Larva**: The second stage, where the insect is in a feeding phase and looks different from the adult.
- **Pupa**: The third stage, where the larva undergoes transformation and is usually inactive.
- **Adult**: The final stage, where the insect emerges with wings and reproductive capabilities.

4. **Analyzing the Options**: We need to identify which of the given options includes insects that undergo complete metamorphosis:
- **Option 1**: Housefly and cockroach - Cockroaches undergo incomplete metamorphosis.
- **Option 2**: Mosquito and cockroach - Again, cockroaches do not undergo complete metamorphosis.
- **Option 3**: Housefly and mosquito - Both of these insects undergo complete metamorphosis.
- **Option 4**: Cockroach and locust - Both of these also undergo incomplete metamorphosis.

5. **Conclusion**: The only option that includes insects that undergo complete metamorphosis is **Option 3: Housefly and mosquito**.

**Final Answer**: Complete metamorphosis occurs in housefly and mosquito.

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