Choose the correct answer :
Acclimatization is :

Options

A. Introduction
B. Pure - line breeding
C. Pure -line selection
D. Adaptation to new environment

Answer

To answer the question "Acclimatization is:", we will analyze the options provided and determine which one correctly defines acclimatization.

### Step-by-Step Solution:

1. **Understanding Acclimatization**: Acclimatization refers to the physiological or behavioral changes that occur in an organism in response to a new environment. These changes help the organism adjust to the new conditions, enhancing its ability to survive.

2. **Analyzing the Options**:
- **Option A: Introduction** - This does not relate to acclimatization.
- **Option B: Pureline breeding** - This refers to a method of breeding and does not define acclimatization.
- **Option C: Pureline selection** - Similar to option B, this is a breeding technique and not related to acclimatization.
- **Option D: Adaptation to new environment** - This option accurately describes acclimatization, as it involves changes that allow an organism to adjust to new environmental conditions.

3. **Conclusion**: Based on the definitions and analysis, the correct answer is **Option D: Adaptation to new environment**.

### Final Answer:
**D. Adaptation to new environment**

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