In the Section "Investigating Life: Does Natural Selection Maintain Cystic

In the section "Investigating Life: Does Natural Selection Maintain Cystic Fibrosis?",what did the scientists conclude from the data represented in the figure?

A) The fewer copies of a defective CFTR gene an organism has,the more resistant it is to cholera toxin.
B) The number of defective CFTR genes was unrelated to cholera resistance.
C) The more cholera toxin an organism was exposed to,the more copies of its CFTR gene that became defective.
D) The more cholera toxin an organism was exposed to,the fewer copies of its CFTR gene that became defective.
E) The more copies of a defective CFTR gene an organism has,the more resistant it is to cholera toxin.