The resistant bacterial cells illustrate what characteristic of life? a) all living things respond to stimuli. b) all living things maintain homeostasis. c) all living things adapt to changes in their environment. d) all living things contain genetic material and reproduce.

The answer is c, All living things adapt to changes in their environment. The nonresistant bacteria dies off because it hasn't adapted, while the resistant bacteria is still ok. It's kind of like the super-flu, but bacterial, not viral.

Your answer would be C. All living things adapt to change in their environment.
 
For instance, if people continuously take antibiotics, then the bacterial cells will slowly start to learn and evolve in a way where they resist these antibiotics. This is actually an issue and if the current bacterial cells resist our current antibiotics, then scientists will need to create a new anti-resistant antibiotic. 

I hope your answer was satisfyingly answered. :)