Genetic engineering aims at:

Options

A. Destroying wild gene
B. Preserving defective gene
C. Curing human disease by introducing new gene
D. All the above

Answer

**Step-by-Step Solution:**

1. **Understanding Genetic Engineering**: Genetic engineering is a field of biotechnology that involves manipulating an organism's genes to achieve desired traits or characteristics. It can involve the introduction, removal, or alteration of genetic material.

2. **Analyzing the Options**:
- **Option A: Destroying wild gene**: Wild genes are the natural, unaltered genes found in populations. The goal of genetic engineering is not to destroy these genes, so this option is incorrect.
- **Option B: Preserving defective gene**: Defective genes are those that may cause abnormal traits or diseases. Genetic engineering does not aim to preserve these genes; rather, it seeks to correct or replace them. Thus, this option is also incorrect.
- **Option C: Curing human disease by introducing new gene**: This option aligns with the primary goal of genetic engineering. By introducing new genes, scientists can potentially cure genetic disorders and improve health outcomes. This is indeed a significant aim of genetic engineering.

3. **Conclusion**: After evaluating all the options, the correct answer is that genetic engineering aims at curing human disease by introducing new genes.

**Final Answer**: Curing human disease by introducing new gene.

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