The hepatitis B virus is common in China relative to other countries in the region. The disease can easily be prevented through vaccination, regulation of barbershop and manicure practices, and health education. Yet, the incidence of this disease continues to rise in China, while it remains stable or is falling in China's neighboring countries.
Which of the following, if true, would best explain the situation described above?
The situation described is that hepatitis B is more prevalent in China than in neighboring countries, even though the disease can easily be prevented. This scenario could be explained by a relevant difference between China and its neighbors.
(A) This choice provides an irrelevant difference. It's too great a leap to assume a link between illegal drug use and the prevalence of hepatitis B.
(B) This choice does not provide a relevant difference. “Accompanying social problems” is too broad to be a specific link to hepatitis B. There are a myriad of social problems that do not involve the incidence of any physical illness.
(C) CORRECT. The statements given indicate hepatitis B prevention methods that are specifically mentioned in the argument. If, unlike its neighbors, China does not employ those methods, it would explain the higher incidence.
(D) This choice does not provide a relevant difference. There is no reason given that would make socialized medicine the cause of the increased incidence. Furthermore, if more people have access to health care, it makes it more puzzling that the incidence is higher.
(E) The findings of twenty years ago are too dated to explain why the incidence is still higher and even rising today.