Genetic engineering is :

Options

A. Plastic surgery
B. Addition or removal of genes
C. Study of extranuclear genes
D. All the above

Answer

**Step-by-Step Solution:**

1. **Understanding Genetic Engineering**: Genetic engineering is a biotechnological process that involves the manipulation of an organism's DNA. This manipulation can include the addition or removal of specific genes to achieve desired traits or characteristics.

2. **Evaluating the Options**:
- **Plastic Surgery**: This option refers to surgical procedures aimed at altering physical appearance and is not related to genetic manipulation. Therefore, it is not a correct answer.
- **Addition or Removal of Genes**: This option accurately describes a fundamental aspect of genetic engineering, where specific genes can be added to or removed from an organism's genome to produce desired traits. This is a key process in genetic engineering.
- **Study of Extra Nuclear Genes**: This option refers to the study of genes located outside the nucleus, such as mitochondrial DNA. While this is a field of study, it does not encompass the broader definition of genetic engineering.
- **All of the Above**: Since not all the previous options are correct, this option cannot be correct either.

3. **Conclusion**: The most accurate description of genetic engineering from the provided options is "addition or removal of genes," as it directly relates to the manipulation of genetic material to achieve specific outcomes.

**Final Answer**: Genetic engineering is the addition or removal of genes.

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