Cystic Fibrosis (CF) Is a Disease Caused by a Mutation

Cystic fibrosis (CF) is a disease caused by a mutation in a gene called the cystic fibrosis transmembrane conductance regulator (CFTR) . The mutation causes the afflicted individual to produce thick, sticky mucus that the lining the respiratory tract can't easily remove. There is no cure for CF, and most individuals suffering from this condition die in their 20s or 30s.
Based on this scenario, what would you conclude about people who have CF?

A) They have excessive growth rates that result in gigantism.
B) They have dangerously high blood pressure.
C) They suffer from incessant coughing and chronic lung infections.
D) They have extremely thin skin that is easily damaged.
E) They have elevated oxygen levels in their blood.