This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
[{'content': 'Pneumococcal resistance to penicillin G is mainly acquired by  : \nSelect and explain. \nA. Conjugation, B. Transduction, C. Transformation, D. All of the above', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Acquisition of antibiotic resistance by Transduction is common in Staphylococcal and that of by Transformation in Pneumococcus and Neisseria.\nVancomycin resistance in enterococci and Staphylococcus is mediated by the conjugative plasmid.', 'role': 'assistant'}]