Teens interested in losing weight, for instance, got advertisements for unhealthy tips on how to become anorexic (厌食者). Such advertisements targeted these kids in hopes of persuading them to try things that were either dangerous or illegal at their age.

Advertisements are just one example of persuasion — trying to change another’s mind. Advertisements may try to convince us to buy something or do something new and different. Marketing is a field of persuasion designed to sell things, notes Jacob Teeny. Persuasion can be used to sell things. At its worst, it can be used to control people. Clearly, persuasion can be used for good and bad.

People open to new experiences tend to be more easily persuaded, Teeny says. But open-minded people can resist some persuasive arguments — such as the idea that eating junk food is cool. And closed-minded people can sometimes be persuaded. “If you haven’t really thought about the arguments” ahead of time, Teeny says, you’re going to be “much more persuadable.”

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What is the main idea of Paragraph 2?

A．Marketing is designed to sell things.

B．Persuasion is used to control people.

C．Persuasion has advantages and disadvantages.

D．We should follow advertisements to buy things.