## **Core Concept**
The question tests understanding of bacterial genetics, specifically the mechanisms of horizontal gene transfer. Bacteriophages, or phages, are viruses that infect bacteria and can facilitate the transfer of bacterial DNA.

## **Why the Correct Answer is Right**
Transduction is the process by which a bacteriophage transfers DNA from one bacterium to another. This occurs when a phage, during its replication cycle, mistakenly packages bacterial DNA instead of its own viral DNA. When this phage infects another bacterium, it can transfer the bacterial DNA, leading to genetic recombination. This process is a significant mechanism for gene transfer among bacteria.

## **Why Each Wrong Option is Incorrect**
- **Option A:** This option is incorrect because transformation refers to the direct uptake of free DNA molecules from the environment by competent bacterial cells. It does not involve a bacteriophage.
- **Option B:** This option is incorrect because conjugation is a process where DNA is transferred directly from one bacterium to another through a specialized structure called a conjugation pilus. It does not involve a bacteriophage.
- **Option D:** This option is incorrect because transfection refers to the process of introducing nucleic acids into eukaryotic cells. While it involves the transfer of DNA, it is not related to bacteria or bacteriophages.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that transduction is particularly significant in the spread of antibiotic resistance genes among bacterial populations. For example, the spread of MRSA (methicillin-resistant *Staphylococcus aureus*) can involve transduction of resistance genes.

## **Correct Answer:** C. Transduction.