Explanation

Reading the question: the substance of this question is to keep track of the points of view and then critique the latter one. The consultant says, roughly, that advertising in videos has shown promise, but we don't recommend it. The client says, roughly, you recommend other things like this, so that can't be right.

Creating a filter: Term matching works here. The client is equating "many forms of advertising that have a potential brand impact" with the subject of their discussion, "advertising in videos purchased for download." But these terms are not quite the same, and, quite possibly, there is a significant difference between these two forms of advertising.

Applying the filter: We'll go out of order. Choice (B) doesn't compare the types of advertising or discuss brand impact, so it's out. Same for choice (C). Choices (A) and (D) are inconsistent with the prompt. They both state something that has already been stated or implied by the consultant and acknowledged by the client. We are left with (E). Can we find grounding in (E)? In this case, the "known risks" are the bad brand ads the consultant has suggested in the past and which the client is bringing up. "Unknown risks" are the bad brand from advertising in videos purchased for download. The client is equating these two things, whereas the consultant is distinguishing them. In fact, (E) fulfilled our prediction, since it touched on the difference we came up with in term matching.

Logical proof: We can apply the negation test to choice (E). If we accept the negation of (E) as fact, then the known risks and the unknown risks could be weighed against each other. In that case, the two types of ads would be comparable, and the client wouldn't be making a mistake at all. The correct answer is (E).