What term refers to the process where viruses infect bacterial cells?

The process where viruses infect bacterial cells is known as transduction. In this context, transduction specifically refers to the mechanism by which bacteriophages (viruses that infect bacteria) transfer genetic material from one bacterium to another. When a bacteriophage infects a bacterial cell, it can incorporate bacterial DNA into its own viral genome. When this phage goes on to infect another bacterial cell, it can transfer this DNA, leading to genetic variation in the recipient bacterium.

Transcription pertains to the synthesis of RNA from a DNA template and does not involve viral infection. Transformation is another process in which bacteria take up free DNA from their environment, which does not involve viruses. Conjugation involves the direct transfer of DNA between two bacterial cells through a physical connection called a pilus, again not involving viruses. Thus, transduction is accurately the only term relevant to the infection of bacterial cells by viruses.