GMAT Critical Reasoning (CR) | Re: It is probably not true that colic in infants is caused by the inabil

It is probably not true that colic in infants is caused by the inability of those infants to tolerate certain antibodies found in cow’s milk, since it is often the case that symptoms of colic are shown by infants that are fed breast milk exclusively.

Which one of the following, if true, most seriously weakens the argument?

(A) A study involving 500 sets of twins has found that if one infant has colic, its twin will probably also have colic.

(B) Symptoms of colic generally disappear as infants