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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Pneumococcal resistance to penicillin G is mainly acquired by  :
assistant
The correct answer is  Acquisition of antibiotic resistance by Transduction is common in Staphylococcal and that of by Transformation in Pneumococcus and Neisseria.
Vancomycin resistance in enterococci and Staphylococcus is mediated by the conjugative plasmid.