In Asia countries, the incidence of liver disease is higher than in non-Asia developing countries. This difference in liver disease rates cannot be due to the greater genetic susceptibility to liver disease amongst Asias, because statistics show that Asians who migrate to Africa countries decrease their chances of getting a liver disease and that those from Africa countries who migrate to Asia increase their chances of getting liver disease. Since there are major differences in diet between Asia and African countries, it is reasonable to conclude that the higher liver disease rates in Asia are due to certain liver-disease-causing foods.Which one of the following, if true, would most weaken the above argument?
选项：

A:People who migrate from African countries to Asia are relatively young and healthy.
B:Northern Asia countries have far lower liver disease rates than countries in Southern Asia.
C:Diet is a contributory cause of many other health problems besides liver disease.
D:Stress is a contributory cause of liver disease and Asians experience higher than average stress in their daily lives.