How Would Methicillin Resistance Arise in a Strain of S

How would methicillin resistance arise in a strain of S.aureus?

A) The methicillin would cause mutations in the bacteria, allowing them to survive
B) The bacteria would sense the methicillin and mutate their DNA to survive
C) The bacteria would mate during asexual reproduction, and some of their offspring could be resistant to the methicilin
D) The bacteria would stop making a cell wall and thus be resistant to the methicillin
E) Bacteria with pre-existing mutations would survive and reproduce