The pythons are inexpensively priced because many of them suffer from the liver disease. Pythons hatched in neither Africa nor North America are not afflicted with the liver disease. Some pythons hatched in North America may appear fine but will die within six months as a result of the liver disease. Pythons that hatch in Africa are more susceptible to the liver disease than are pythons that hatch in North America.
Two months ago a major shipment of pythons arrived from Africa, resulting in a great number of inexpensive pythons in pet stores. Anyone interested in buying a python, however, should beware: many pythons hatched in Africa are afflicted with a deadly liver disease. Although a few pythons recently hatched in North America have this disease, a much greater proportion of African-hatched pythons have it. The disease is difficult to detect in its early stages, and all pythons die within six months of contracting the disease.
Which one of the following statements can be properly inferred from the statements above?