A patient with a bacterial infection is treated with an

antibiotic to which the pathogen is classified as “susceptible.” The infection

resolves slowly, and viable bacteria can still be isolated midway through

treatment. Genomic analysis shows no resistance mutations, and post‑treatment

isolates remain fully susceptible in vitro. Tolerance is identified as the

underlying phenotype.

If this treatment scenario is common in a hospital setting

over many years, which evolutionary outcome is most likely?