Which of the following statement/s is/are and example of genetic engineering?
I. Inserting a gene for human insulin production into bacteria.
II. Selective breeding to produce cattle with high milk yields.
III. Using methods like crop rotation with leguminous plants to increase the fertility of the soil.
IV. Vegetative propagation and grafting are practised to ensure higher yield.

Options

A. I, II and IV
B. II and III
C. I and III
D. Only I

Answer

To determine which of the statements is an example of genetic engineering, let's analyze each statement step by step.

### Step-by-Step Solution:

1. **Statement I: Inserting a gene for human insulin production into bacteria.**
- This is an example of genetic engineering. It involves the use of recombinant DNA technology, where a specific gene (in this case, the gene for human insulin) is inserted into the DNA of bacteria. This allows the bacteria to produce human insulin, which is a direct application of genetic engineering.

2. **Statement II: Selective breeding to produce cattle with high milk yields.**
- This is NOT an example of genetic engineering. Selective breeding involves choosing specific parents with desirable traits to produce offspring with those traits. It is a traditional method of improving species but does not involve direct manipulation of the organism's DNA.

3. **Statement III: Using methods like crop rotation with leguminous plants to increase the fertility of the soil.**
- This is also NOT an example of genetic engineering. Crop rotation and the use of leguminous plants are agricultural practices aimed at improving soil fertility through natural processes, such as nitrogen fixation. This does not involve altering the genetic material of the plants.

4. **Statement IV: Vegetative propagation and grafting are practiced to ensure higher yield.**
- This is NOT an example of genetic engineering either. Vegetative propagation and grafting are traditional horticultural techniques used to reproduce plants and enhance yields, but they do not involve genetic modification at the molecular level.

### Conclusion:
Based on the analysis:
- Only **Statement I** is an example of genetic engineering.
- Therefore, the correct answer is **Option I only**.