When the genotype of an organism is improved by the addition of foreign gene, the process is called

Options

A. Tissue culture
B. Genetic diversity
C. Genetic engineering
D. Plastic surgery

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the process that involves improving the genotype of an organism through the addition of a foreign gene.

2. **Identifying Key Terms**: The key terms here are "genotype," "improved," and "foreign gene." The genotype refers to the genetic makeup of an organism, and the addition of a foreign gene suggests a manipulation of this genetic material.

3. **Analyzing the Options**:
- **Tissue Culture**: This process involves growing cells or tissues in a controlled environment, primarily used in plant propagation. It does not involve altering the genotype with foreign genes.
- **Genetic Diversity**: This term refers to the variety of genes within a population. It does not pertain to the addition of foreign genes to improve genotype.
- **Genetic Engineering**: This is the process of directly manipulating an organism's DNA by adding, removing, or altering genetic material. This fits the description of improving genotype through the addition of a foreign gene.
- **Plastic Surgery**: This is a medical procedure aimed at reconstructing or altering the human body, which is unrelated to genetic manipulation.

4. **Conclusion**: Based on the analysis, the correct answer is **Genetic Engineering**. This process specifically involves the addition of foreign genes to improve or alter the genotype of an organism.

**Final Answer**: Genetic Engineering

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