Transgenic plants are developed by

Options

A. Introducing foreign genes
B. Introducing gene mutations
C. Deleting certain chromosome parts
D. Stopping spindle formation.

Answer

### Step-by-Step Solution:

1. **Understanding Transgenic Plants**: Transgenic plants are defined as plants that have been genetically modified to contain genes from other organisms. This modification is achieved through genetic engineering techniques.

2. **Identifying the Process**: The primary method for developing transgenic plants involves the introduction of foreign genes into the plant's genome. This is done using recombinant DNA technology, which allows scientists to insert specific genes that confer desirable traits.

3. **Evaluating the Options**:
- **Introducing foreign genes**: This is the correct method for creating transgenic plants.
- **Introducing gene mutations**: While mutations can occur naturally or be induced, they do not specifically create transgenic plants.
- **Deleting certain chromosome parts**: This does not align with the definition of transgenic plants, as it involves removing genetic material rather than adding it.
- **Stopping spindle formation**: This option relates to cell division and does not pertain to the creation of transgenic plants.

4. **Conclusion**: Based on the evaluation of the options, the correct answer is that transgenic plants are developed by **introducing foreign genes**.

### Final Answer:
Transgenic plants are developed by introducing foreign genes.

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