Black Americans are, on the whole, about twice as likely as White Americans to develop high blood pressure. This likelihood also holds for westernized Black Africans when compared to White Africans.
Researchers have hypothesized that this predisposition in westernized Blacks may reflect an interaction between western high-salt diets and genes that adapted to an environmental scarcity of salt.
Which of the following statements about present-day, westernized Black Africans, if true, would most tend to confirm the researchers’ hypothesis?
(A) The blood pressures of those descended from peoples situated throughout their history in Senegal and Gambia, where salt was always available, are low.
答案是A，我通过排除法剩下的答案是A，但是经过仔细分析我始终不知道为什么此答案可以confirm the researchers’ hypothesis，请各位NN门帮忙看一下
多谢了。 | 
