When organisms change their location to escape from harsh environment, it is called as

Options

A. hibernation
B. vernalisation
C. migration
D. aestivation

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question:** The question asks for the term used when organisms change their location to escape from a harsh environment.

2. **Identifying the Context:** Organisms face various environmental challenges, and they have developed strategies to cope with these challenges. The question specifically refers to the movement of organisms to avoid harsh conditions.

3. **Considering the Options:** The two main strategies organisms use to deal with harsh conditions are migration and dormancy.

4. **Defining Migration:** Migration refers to the movement of large populations or groups of animals from one location to another, typically in response to environmental changes. This movement is often seasonal and allows organisms to find more favorable living conditions.

5. **Examples of Migration:** Many species, including birds, fish, and insects, exhibit migratory behavior. They move to areas with better resources, such as food and shelter, and return when conditions improve.

6. **Conclusion:** Based on the definition and examples, the correct term for when organisms change their location to escape from harsh environments is "migration."

**Final Answer:** Migration

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