The columnist tells us that it's impossible for there to be real evidence that lax radiation standards at nuclear reactors contributed to increased cancer rates near these sites. The columnist supports this assertion by saying that there are so many other potential causes of cancer that we can't really know which of these factors caused cancer in these people.
The problem with the columnist's argument is that he's failing to take into account that even though it might be nearly impossible to identify a single cause of what caused an individual case of cancer, it is possible to observe statistical trends in the rates of cancer for areas near the nuclear reactor sites. If these areas have cancer rates that are vastly larger than surrounding areas, then that would suggest that the lax radiation standards may have contributed to increased cancer rates near the reactors.
The question says, "The argument's reasoning is most vulnerable to criticism on which one of the following grounds?"
We're looking to identify the flaw of the argument.
(A) says, "The argument fails to recognize that there may be convincing statistical evidence even if individual causes cannot be known."
This is just what we'd been anticipating. Even though we may not be able to tell what the cause for a single case of cancer was, this doesn't mean that there can't be convincing evidence of a trend near the site. Remember, the columnist has a really strong conclusion ("it is impossible for there to be real evidence...") and providing statistical evidence showing a trend with increased cancer rates near the sites would certainly qualify as evidence that he's purporting to be impossible. (A) picks up on exactly the flaw of the columnist's thinking, and it's our correct answer choice.
Does this make sense? Let us know if you have any more questions!
