When an alien DNA fragment is linked with the origin of replication, so that this alien piece of DNA can replicate and multiply itself in the host organism, then this can be called as

Options

A. gene transfer
B. gel electrophoresis
C. gene cloning
D. transformation

Answer

To solve the question, we need to understand the concepts involved with the alien DNA fragment and its replication in a host organism. Here’s a step-by-step breakdown of the solution:

### Step 1: Understand the Question
The question asks about a scenario where an alien DNA fragment is linked with the origin of replication, allowing it to replicate and multiply in a host organism.

### Step 2: Identify Key Terms
- **Alien DNA Fragment**: This refers to DNA that is not originally from the host organism.
- **Origin of Replication**: This is a specific sequence in the DNA where replication begins.
- **Replicate and Multiply**: This indicates that the DNA is being copied and increased in number within the host.

### Step 3: Analyze the Options
1. **Gene Transfer**: This refers to the movement of genetic material between organisms, but does not specifically imply replication.
2. **Gel Electrophoresis**: This is a technique used to separate DNA fragments based on size; it is not related to replication.
3. **Gene Cloning**: This involves making identical copies of a specific DNA segment, which aligns with the idea of replicating the alien DNA in the host.
4. **Transformation**: This is a process where a cell takes up foreign DNA from its environment, but it does not necessarily imply replication.

### Step 4: Conclusion
Since the question specifies that the alien DNA is linked to the origin of replication and is able to replicate and multiply, the most appropriate term that describes this process is **gene cloning**. This process results in the creation of multiple identical copies of the alien DNA.

### Final Answer
The correct answer is **Option 3: Gene Cloning**.

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