Haven't understood the question yet.

Hi, the author tries to tell us that we should avoid irradiated food for several reasons. A weakens the argument by showing that one of the negative consequences that the author cites is extremely rare. B does not weaken the argument, and is thus correct. C contradicts one of the negative effects the author cites of irradiation. D shows that a harmful effect the author shows is not more harmful than for food that is not irradiated. E directly refutes the idea that irradiated foods cause cancer.

I am still confused by this question and feel that there may be an error here. Option B on the practice test reads: "Cancer and other serious health problems have many causes that are unrelated to radioactive substances and gamma rays." Option B when you click "view question" within the discussion tab reads: "The amount of harmful chemicals found in irradiated foods is less than the amount that occurs naturally in most kinds of foods."