Read the excerpt from "Ads: Why We Buy What We Buy," and observe the boldfaced evidence to support the main argument. Between ages 15 and 25, he notes, we are particularly eager to spend our money, on everything from just the right haircut to just the right jeans, because boys want to impress girls and vice versa. It is, says Twitchell, much like male birds showing off their brightly colored feathers to females.

The main argument is that advertisers understand what motivates people to shop.

Which answer best uses the evidence to evaluate the main argument?

The argument is ineffective; the evidence shows it's only possible to predict the behaviors of animals.

The argument is ineffective; the evidence refers to background knowledge that may not be widely known.

The argument is effective; the evidence points out that advertisers study animals to understand people.

The argument is effective; the evidence shows that humans buy things to draw attention to themselves.