This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General, Subject name: Microbiology
[{'content': 'A nonspore-forming, gram-positive bacillus was isolated from a throat specimen from a primary school-aged child who had not been vaccinated with the DTaP vaccine. The strain isolated carried a bacteriophage on which the gene for toxin was encoded. How did this strain become toxigenic? \nSelect and explain. \nA. Conjugation, B. Frameshift mutation, C. Homologous recombination, D. Transduction', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Transduction (d) is the transfer of DNA mediated by bacteriophages. In generalized transduction, the phage virus can carry any segment of the donor chromosome; in specialized transduction, the phage carries only specific genes, generally those immediately adjacent to the site of prophage insertion.', 'role': 'assistant'}]