An Adaptive Walk of Beta-Lactamase in Response to Selective Pressure

Multiple Choice

An adaptive walk of beta-lactamase in response to selective pressure exerted by cefotaxime likely involved:

A) the random generation of five changes that provide microbial resistance to the antibiotic.
B) sequential changes in single amino acids that each provided an incremental level of resistance to the antibiotic.
C) increased genetic change induced by selective pressure exerted by the antibiotic.
D) one clear beneficial change and several non-impactful changes in the gene.
E) major shifts in the metabolic pathways in the microbe under selection.