This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Chemotherapy, Subject name: Pharmacology
[{'content': 'Drug resistance transmitting factor present in bacteria \nSelect and explain. \nA. Plasmid, B. Chromosome, C. Introns, D. Centromere', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ref KDT 6/e p671 Plasmids contain extra chromosomal DNA that help in transforming the gene responsible for multiple drug resistance among bacteria These are therefore involved in horizontal transfer not resistance', 'role': 'assistant'}]