In animal pure lines can be evolved by practicing

Options

A. inbreeding
B. cross breeding
C. out breeding
D. AI

Answer

### Step-by-Step Solution:

1. **Understanding Pure Lines**:
- Pure lines refer to a population of organisms that exhibit uniform characteristics without any variation. This means that all individuals in the pure line show the same traits.

2. **Inbreeding Definition**:
- Inbreeding is the practice of mating closely related individuals within the same species. This method is used to produce offspring that are genetically similar.

3. **Purpose of Inbreeding**:
- The main goal of inbreeding is to identify and eliminate harmful recessive genes. These are genes that may not express themselves in a heterozygous state but can appear in the next generation if two carriers mate.

4. **Elimination of Undesirable Genes**:
- Through the process of selection during inbreeding, breeders can eliminate undesirable genes from the population. This is crucial for maintaining the health and viability of the pure line.

5. **Accumulation of Superior Genes**:
- Inbreeding also facilitates the accumulation of superior genes, which are beneficial traits that enhance the quality of the population. This is important for improving desirable characteristics in the breed.

6. **Conclusion**:
- Therefore, to evolve pure lines in animals, the practice of inbreeding is essential. It helps in both the elimination of harmful genes and the enhancement of desirable traits.

### Final Answer:
In animal pure lines can be evolved by practicing **inbreeding**.

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