An Antibiotic Kills 99

An antibiotic kills 99.9% of a bacterial population. What will be the result of the continued application of this antibiotic?

A) Every time the antibiotic is given, it will kill 99.9% of the bacterial population.
B) Through time, the antibiotic will become less effective at killing the bacteria.
C) Eventually, the entire bacterial population will be wiped out.
D) The bacterial population will reach an equilibrium point at which the antibiotic is 50% effective.