[原创]请牛人指点,我找不到题号

Which of the following most logically completes the argument given?
 
People in isolated rain-forest communities tend to live on a largely vegetarian diet, and they eat little salt.  Few
of them suffer from high blood pressure, and their blood pressure does not tend to increase with age, as is
common in industrialized countries.  Such people often do develop high blood pressure when they move to cities
and adopt high-salt diets.  Though suggestive, these facts do not establish salt as the culprit in high blood
pressure, however, because _____.

      A  genetic factors could account for the lack of increase of blood pressure with age among such people

      B  people eating high-salt diets and living from birth in cities in industrialized societies generally have a
      tendency to have high blood pressure

      C  it is possible to have a low-salt diet while living in a city in an industrialized country

     D   there are changes in other aspects of diet when such people move to the city

     E   salt is a necessity for human life, and death can occur when the body loses too much salt

我倾向选D.就是要反对原文说的"salt是blood pressure 升高的原因".D就是说搬到城市里面后,饮食上除了salt之外还有其它的改变,不一定就是salt引起blood pressure 升高的.

A说blood pressure 没有升高是基因,这和搬到城市里面后blood pressure 升高不一致.

其它的也不对.

楼主这题没有答案吗?

答案就是D

多谢,我就是选的A,一看我就以为是他因,结果这个genetic factor一下就把我吸引了，就没仔细想.

谢谢

Although the discount stores in Goreville's central shopping district are expected to close within five years as a result of competition from a SpendLess discount department store that just opened, those locations will not stay vacant for long.  In the five years since the opening of Colson's, a nondiscount department store, a new store has opened at the location of every store in the shopping district that closed because it could not compete with Colson's.
 
Which of the following, if true, most seriously weakens the argument?

A   Many customers of Colson's are expected to do less shopping there than they did before the SpendLess store opened.

B   Increasingly, the stores that have opened in the central shopping district since Colson's opened have been discount stores.

C   At present, the central shopping district has as many stores operating in it as it ever had.

D   Over the course of the next five years, it is expected that Goreville's population will grow at a faster rate than it has for the past several decades.

E   Many stores in the central shopping district sell types of merchandise that are not available at either SpendLess or Colson's.

刚才那位牛人还在吗，我再问一道,多谢多谢~

请楼主重开一贴,并标名题号.造福后来人.

谢谢!