题目内容：

Now, short videos（视频）are popular among students. They have millions of views（浏览）online. Many people share short videos on video apps like Douyin and Kuaishou. You can even add（增加）music and special effects （特效）to your videos. The videos are 15 seconds to a few minutes long. They show people doing activities like cooking, exercising and singing.

High school students enjoy these videos very much. More than 50% of first- and second-year junior high school students said they enjoy watching these short videos. About 47% posted their own videos, according to（根据）a survey by the China National Youth Palace Association.

The videos let high school students see funny and exciting things. Many students like to share the fun things with others, too. For example, a 12-year-old girl named Xiaoqianyu posted videos showing her learning jazz dance. This helps her win many fans.

However, some students spend too much time watching them and not enough time studying. Some videos have vulgar content（低俗的内容）and it is not good for students. To solve this problem, Douyin added a new function（功能）in April. The app will be closed if someone uses it for over two hours a day.

1.According to the passage, what can kids add to their short videos with these apps?

A. Special effects.    B. Vulgar content.    C. Homework.    D. Unhealthy videos.

2.How long are the short videos?

A. 15 seconds.    B. 15 minutes.    C. 15 hours.    D. 15 days.

3.How many junior high school students posted their own videos?

A. 50%.    B. 47%.    C. 15%.    D. 12%.

4.What will happen if students spend too much time watching short videos?

A. They will become funny.    B. They will learn to dance jazz.

C. They will win many fans.    D. They will have less time to study.

5.What’s the best title of the passage?

A. Making Short Videos    B. Sharing Your Short Videos

C. Crazy for Short Videos    D. Short Videos’ New Functions