A bacterial population within a chronic wound exhibits increasing resistance to a topical antibiotic. Which mechanism explains why this resistance spreads, even without new bacteria entering the wound?

💡 Explanation

The increased antibiotic resistance arises from mutations conferring resistance, followed by horizontal gene transfer of these resistance genes to other bacteria in the population. This spreads resistance quickly because resistance genes are transferred rather than relying solely on slower clonal expansion of the original mutant cell; therefore, option C is correct.

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