Critical Reasoning (CR) | Re: The caterpillar of the monarch butterfly feeds on milkweed plants, who

The caterpillar of the monarch butterfly feeds on milkweed plants, whose toxins make the adult monarch poisonous to many predators. The viceroy butterfly, whose caterpillars do not feed on milkweed plants, is very similar in appearance to the monarch. Therefore, it can be considered that the viceroy is so seldom preyed on because of its visual resemblance to the monarch.

Which of the following, if it were discovered to be true, would most seriously undermine the argument?

(A) Some predators do
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