試題詳解

14.If the bacterium Staphylococcus aureus experiences a cost for maintaining one or more antibiotic-resistance genes, what would happen in environments that lack antibiotics?
(A) These bacteria would be outcompeted and replaced by bacteria that have lost these genes.
(B) These bacteria would try to make the cost worthwhile by locating and migrating to microenvironments where traces of antibiotics are present.
(C) The number of genes conveying antibiotic resistance would increase in these bacteria.
(D)These genes would be maintained in case the antibiotics appear.