题目内容：

    Food companies engineer junk food to make it addictive. They label their products to make them seem much healthier than they are. Their advertisements target children. All of this is according to a news report read recently by students in a Texas middle school. They were taking part in an experiment run by the University of Chicago and the University of Texas. “I don't understand how this is even legal, ” said a girl who took part in the study.

Researchers had students learn about food-industry advertising strategies. They wanted to know if learning about them would change how kids feel about junk food. All over the world, kids are eating more foods that are high in salt, sugar, and fat. That is partly the result of clever ads that make junk food irresistible. Christopher J. Bryan led the study. He says that when kids question the motives behind junk food ads, they feel like they're fighting injustice. The reward is knowing they are doing the right thing.

Junk food has been linked to health problems such as heart disease, obesity, and diabetes，But in 2018，food companies spent nearly $9 billion TV ads selling unhealthy fare. Companies use varying strategies. An ad with cartoon characters may make chips seen fun to eat. A professional athlete enjoying a sugary drink may make it look cool. Advertisers                know that if kids want a product, they'll annoy their parents to buy it. Even parents don't notice the power of ads. By the time they are adults they have been used to junk-food advertising. They just don't see it.

In the Texas study, Bryan had students view ads on iPad. Their job was to write or draw on the screen, to make each ad's message true. For example, a McDonald's ad showed a Big Mac (巨无霸) and the words “The thing you want when you order salad. ” To the end of the sentence, a student added “should be salad”.

Three months after analyzing ads, students were still choosing healthier snacks: milk instead of sugary juices, fruit over cookies. Kids are becoming conscious of themselves as agents in the world. They see a chance to make the world a better place.

1.What is the purpose of the experiment?

A.To survey what snacks children like best. B.To guide children against unhealthy food.

C.To find ways to make junk food healthy. D.To teach children how to pick out legal food.

2.How do children feel about junk food advertisements after the experiment?

A.Cool. B.Legal.

C.Funny. D.Misleading.

3.Why are parents unaware of the harm of junk food advertisements?

A.Parents have never seen such junk food advertisements.

B.Advertisements have blinded them since they were young.

C.The food industry has special advertising strategies for parents.

D.Parents have to agree with their children about the junk food.

4.How did students conduct the experiment?

A.By correcting unreal advertisements. B.By offering suggestions to food industry.

C.By making up their own advertisements. D.By studying food industry advertising strategies.