Premise: people who drink camelia tea are more likely than people in general to develop kidney damage.
Conclusion: consumption of this tea results in a heightened risk of kidney damage.
Tea made from camellia leaves is a popular beverage. However, studies show that regular drinkers of camellia tea usually suffer withdrawal symptoms if they discontinue drinking the tea. Furthermore, regular drinkers of camellia tea are more likely than people in general to develop kidney damage. Regular consumption of this tea, therefore, can result in a heightened risk of kidney damage.
Which one of the following, if true, most seriously weakens the argument?
(A) Several other popular beverages contain the same addictive chemical that is found in camellia tea.
The conclusion does not pertain to any sort of interaction with addictive chemicals or the addictive properties of camelia tea. (B) Addictive chemicals are unlikely to cause kidney damage solely by virtue of their addictive qualities.
The same logic for A can be applied here. We're not really looking for an effect caused by the addictive chemicals in camelia tea.
(C) Some people claim that regular consumption of camellia tea helps alleviate their stress.
That's fine. However, this would not help weaken the conclusion that consumption of camelia tea causes kidney damage. (D) Most people who regularly drink camellia tea do not develop kidney damage.
But some do, therefore "regular drinkers of camellia tea are more likely than people in general to develop kidney damage"(E) Many people who regularly consume camellia tea also regularly consume other beverages suspected of causing kidney damage.
We have found a variable that covaries with the consumption of camelia tea. More specifically, people who consume camelia tea also consume beverages that are suspected of causing kidney damage. This doesn't necessarily disprove the conclusion, but it certainly provides grounds for further exploration as to whether the consumption of camelia tea causes kidney damage. Thus, the conclusion is weakened. *An important point - the discussion of withdrawal symptoms is merely meant to confuse the reader. It also allows for 1 or 2 trap answer choices, namely A and B.