Some antibiotics used to treat infections in humans are also used to treat chickens, but some groups oppose this practice. The overuse of the antibiotics will most likely influence the natural selection of which type of organisms?

Bacteria resistant to the antibiotics

Explanation:

Overuse of antibiotics has been proven to increase the mutation rates of bacteria population. The increased mutation increase the chances of developing a strain of bacteria that is resistant to the antibiotic. This eventually renders the antibiotic ineffective hence opening up risk for a health epidemic catastrophe.