A current challenge for doctors involves the bacterial strain Clostridioides difficile, which no longer responds to traditional antibiotic treatments. Which of the following best explains why this particular strain of bacteria is resistant to antibiotic treatment?

A. Mutations creating new alleles occur more frequently in this species of bacteria than in other species.

B. Crossing over during meiosis increased genetic variability in the bacteria.

C. The bacteria have high genetic variability and high reproductive rates.

D. The bacteria are able to recognize and destroy the antibiotics by breaking them down extracellularly.