Is anyone smart enough to answer this impossible question?
over the past 50 years, natural selection has caused populations of an infectious bacterium to evolve resistance to most antibiotics. if antibiotic use were stopped, which of the following is most likely to occur within the bacteria populations?

the bacterium will go extinct without the presence of antibiotic.

the frequency of nonresistant forms will decrease in these population.

the bacteria populations will begin colonizing new environments.

the frequency of resistant forms will decrease in these populations.

The bacteria populations will begin colonizing new environments & The frequency of resistant forms will decrease in these populations.

Explanation:

The use of antibiotics makes the bacterium population or bacteria resistant to those antibiotics. Bacterium population stays on a type of environment that is formed by using antibiotics.

If antibiotic use were stopped, they would get another type of environment where they can increase there population in another way. Along with this, if antibiotics using were stopped, they wouldn't be able to become resistant because no mutation would occur due to the antibiotics' effect on them.

So, we can say that two occurrences could happen, one is the frequency of resistant forms will decrease in these populations, and another one is the bacteria populations will begin colonizing new environments because we can't predict that any natural mutation would happen or not on this population.