Crossing of unrelated pure breeding animals of different traits within the same breed is called

Options

A. Cross breeding
B. Out crossing
C. Close breeding
D. Species hybridisation

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the term used for the crossing of unrelated pure breeding animals of different traits within the same breed.

2. **Defining Breeding**: Breeding is the process of sexual reproduction between male and female animals (or plants). It can be categorized into two main types: inbreeding and outbreeding.

3. **Inbreeding Explanation**: Inbreeding involves the mating of related animals, where both parents share a close genetic relationship. This is not what the question is asking about.

4. **Outbreeding Explanation**: Outbreeding, on the other hand, involves the mating of unrelated animals. This can be further divided into three types: outcrossing, crossbreeding, and interspecific hybridization.

5. **Identifying Outcrossing**: Outcrossing specifically refers to the crossing of unrelated pure breeding animals within the same breed. This introduces unrelated genetic material into the breeding line, enhancing genetic diversity and reducing the likelihood of genetic diseases or abnormalities.

6. **Conclusion**: Since the question specifically asks for the crossing of unrelated pure breeding animals within the same breed, the correct term is **outcrossing**.

**Final Answer**: The crossing of unrelated pure breeding animals of different traits within the same breed is called **outcrossing**.

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