Which of the following is a common mechanism by which bacteria develop resistance to antibiotics?

Bacteria can develop resistance to antibiotics through various mechanisms, and all the options presented are valid pathways for this development.

Gene duplication allows bacteria to acquire multiple copies of genes, which can sometimes lead to the production of proteins that confer resistance. For instance, if a gene that codes for a target of an antibiotic is duplicated, it may lead to overexpression of altered proteins that either evade the drug's action or can contribute to detoxification.

Mutational resistance involves alterations in the bacterial genome that can lead to changes in proteins targeted by antibiotics. For example, a single mutation in the gene encoding a protein that an antibiotic targets can change the shape of that protein enough to prevent the antibiotic from binding effectively, allowing the bacteria to survive despite the presence of the drug.

Mechanism alteration refers to various strategies by which bacteria can change their metabolic pathways or efflux systems in response to antibiotic pressure. For instance, bacteria may alter the permeability of their cell membranes to prevent antibiotics from entering or increase the expression of efflux pumps to expel the antibiotic quickly before it can exert its effects.

Since each of these mechanisms can independently contribute to bacterial resistance, it is accurate to say that all of them collectively highlight the diverse strategies bacteria use to survive in the presence of antibiotics