3. A man spent 10 years as a laborer in the ship building industry where he was exposed to
fiberglass and asbestos. When he reached the age of 40 he was diagnosed with a lung disease.
While he was undergoing testing, it was also determined that he carried an allele for cystic
fibrosis, giving his employer the opportuinty to argue that his condition was not the result of a
workplace hazard. What would be a logical argument to support the idea that his condition
was caused by environmental factors?
A. The allele for cyctic fibrosis was identified by testing, not by symptoms.
B. The allele for cystic fibrosis was identified after his symptoms appeared.
C. The allele for cystic fibrosis would only cause the disease in his children.
D. The allele for cystic fibrosis would have caused symptoms even without his working with
environmental hazards.