The correct answer here should be E. The first step to solve this question is to identify that it's an inference question, which means you'll be supplying a conclusion that MUST be true. The best way to solve such questions is to try to prove the option false. If it can be false in any circumstance, we can't say that it must be true. If it cannot be false in any circumstance, there's your answer.

A - The argument only tells us that most web users ignore the results. This does not, however, mean that they consider these results illegitimate. Hence, we can't say that this would be true for sure. OUT

B - This option is wildly off base. It is not suggested anywhere that the visibility can increase for less pay for any given type of advertising, and quite the opposite in fact. OUT

C - This is made to sound like online advertising is only for online products. But all we need is to think of a situation that doesn't match this, for example, advertising lawnmowers online. It's probably easier to buy one online since it can be delivered to you, but they don't provide any online service. Hence, C does not add up. OUT

D - The same logic in C holds true here as well. It's not necessary that online businesses would gain more from online ads. What the product offers and how it is advertised have little correlation for this question. OUT

E - This must be correct by process of elimination. But let us confirm nonetheless. The claim made here is very mild: spend more or risk missing out on customers. And this is true of any advertising actually. In particular, this can never be false because advertisers know that every bit of money they spend gives them potential sales, since the targets are already qualified. Hence, it's never NOT a trade-off. This answer is therefore CORRECT.

Remember that the right answer must always be true, and it is much harder to prove that than it is to falsify something. So you're best off trying to prove an option wrong to eliminate it.

- Matoo
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