Animals undergo inactive stage during winters. It is called

Options

A. Acclimatisation
B. Hibernation
C. Aestivation
D. Adaptation

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the term used to describe the inactive state that animals undergo during winter.

2. **Identifying the Options**: The options provided are:
- Acclimatization
- Hibernation
- Activation
- Adaptation

3. **Defining Each Term**:
- **Acclimatization**: This refers to reversible changes in an organism's body that help it adjust to a changing environment. For example, an increase in red blood cell count at high altitudes.
- **Hibernation**: This is a period of inactivity that many animals enter during winter to survive harsh conditions. For instance, polar bears hibernate to conserve energy when food is scarce.
- **Estivation**: This is the opposite of hibernation, where animals become inactive during the summer months to avoid extreme heat.
- **Adaptation**: These are permanent traits that have evolved in organisms over time, allowing them to survive in their specific habitats, such as fins in fish for swimming.

4. **Analyzing the Relevant Term**: Since the question specifically mentions inactivity during winter, the term that fits this description is "hibernation".

5. **Conclusion**: Therefore, the correct answer to the question is **hibernation**.

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