The cells which have the ability to incorporate foreign DNA within them are called:

Options

A. water-loving cells
B. competent cells
C. plasma cells
D. hydrophobic cells

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the type of cells that can incorporate foreign DNA into their own genetic material.

2. **Identifying Key Terms**: The key terms in the question are "incorporate," "foreign DNA," and "cells." This indicates that we are looking for a specific type of cell that has the ability to take up and integrate DNA from outside sources.

3. **Analyzing the Options**: The options provided are:
- Water loving cells
- Competent cells
- Plasma cells
- Hydrophobic cells

4. **Defining Each Option**:
- **Water loving cells**: This term generally refers to hydrophilic substances but does not specifically relate to DNA incorporation.
- **Competent cells**: These are cells that have the ability to take up foreign DNA from their environment and incorporate it into their own genome.
- **Plasma cells**: These are a type of white blood cell that produces antibodies; they do not incorporate foreign DNA.
- **Hydrophobic cells**: This term refers to cells that repel water; it does not relate to the incorporation of DNA.

5. **Selecting the Correct Answer**: Based on the definitions and the ability to incorporate foreign DNA, the correct answer is **competent cells**.

6. **Conclusion**: Competent cells are specifically designed to take up foreign DNA, making them essential in biotechnology for processes such as cloning and genetic engineering.

**Final Answer**: The cells which have the ability to incorporate foreign DNA within them are called **competent cells**.

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