Many vaccines create immunity to viral diseases by introducing a certain portion of the disease–causing virus's outer...

Catherine on September 28 at 12:11PM

I was between A and E

I felt like reading both answers gave me the same answers in a way... essentially being even though people were exposed they did not contract the disease. Please explain

1 Reply

Ravi on October 1 at 08:38PM

@CMarr, (E) is incorrect because it strengthens the argument. It shows that permanent immunity developed in an analogous situation. (A) is correct because it serves to weaken the argument by showing that the method described (which is mimicking the disease in a certain way) is not likely to produce permanent immunity. If it were likely to produce permanent immunity, then these people who were exposed to hepatitis E should not have later gotten it.