I missed this one and would like help with it.
It is a necessary assumption question.
Core is:
People that browse web for med info often cannot discriminate between scientifically valid and quackery info. The quackery is appealing because it is written more clearly than scientific papers.
----->
Therefore, people who rely on the web when attempting to diagnose their med condition are likely to do themselves more harm than good.
What initially jumped out to me on this stimulus was the jump in the conclusion about "people who rely on the web when attempting to diagnose their med condition"....whereas in the stimulus we were simply told of people that browse the web for med info. Two totally different things.
Thus my reason for jumping on choice A.
A negation of (A): People who browse the web for med information typically do NOT do so in attempt to diagnose their med condition.
I felt that this severed the premise link to the conclusion, thus making it necessary to conclude something about people who rely on the web to diagnose med condition.
I do not understand how (B) is necessary:
First, a diagram of (B):
People who attempt to diagnose their medical conditions are NOT likely to do themselves more harm than good ---> They rely exclusively on scientifically valid information
So to negate that:
Even if people who attempt to diagnose their medical conditions are not likely to do themselves more harm than good ---> They DO NOT rely exclusively on scientifically valid information
That does not seem to destroy anything. That does not mean that these people are relying on quackery.