The transformation of the larva into an adult through drastic changes is called :

Options

A. Metamorphosis
B. Metamorphic
C. Fusion
D. None of these

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the transformation of larvae into adults through drastic changes. This indicates a process where the organism undergoes significant physical changes during its development.

2. **Identifying Growth Types**: There are two main types of growth in organisms: direct and indirect. Direct growth means the young ones resemble their parents closely at birth, while indirect growth involves a more complex transformation.

3. **Explaining Indirect Development**: In indirect development, the organism goes through various stages that look very different from the adult form. This is characterized by distinct morphological changes.

4. **Example of Indirect Development**: A classic example is the life cycle of a frog. It starts from an egg, which hatches into a larva (tadpole). The tadpole undergoes significant changes (metamorphosis) to become an adult frog.

5. **Defining Metamorphosis**: The term used to describe the transformation from larva to adult, involving drastic changes in form and structure, is called "metamorphosis."

6. **Conclusion**: Therefore, the transformation of the larva into an adult through drastic changes is called **metamorphosis**.

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