True and complete metamorphosis occurs in

Options

A. Silver
B. Bed bugs
C. Grasshoppers
D. Moths and mosquitoes.

Answer

To answer the question regarding true and complete metamorphosis, we need to understand the concepts of metamorphosis in the animal kingdom.

### Step-by-Step Solution:

1. **Understanding Metamorphosis**:
- Metamorphosis is a biological process by which an animal undergoes a significant change in form or structure after birth or hatching. There are two main types: incomplete (or simple) metamorphosis and complete metamorphosis.

2. **Types of Metamorphosis**:
- **Incomplete Metamorphosis**: This involves three stages: egg, nymph, and adult. The nymph resembles a smaller version of the adult and gradually develops into the adult form.
- **Complete Metamorphosis**: This involves four distinct stages: egg, larva, pupa, and adult. The larval stage looks completely different from the adult and undergoes a transformation during the pupal stage.

3. **Identifying Organisms with Complete Metamorphosis**:
- Organisms that exhibit complete metamorphosis include insects such as butterflies, beetles, and flies. In these organisms, the larval stage (caterpillar for butterflies, grub for beetles) is followed by a pupal stage (chrysalis for butterflies, pupa for beetles) before emerging as an adult.

4. **Conclusion**:
- Therefore, true and complete metamorphosis occurs in insects like butterflies and beetles, which undergo the full cycle of egg, larva, pupa, and adult.

### Final Answer:
True and complete metamorphosis occurs in insects such as butterflies and beetles.

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