阅读下列材料，从每题所给的A、B、C三个选项中选出最佳选项。

What should you do when you can’t find the time to do a long workout? Have you heard of exercise snacks （零食式锻炼）?

Exercise snacks are a popular and inventive new way for people to stay fit. Instead of spending hours on the playground, people break that “large meal” into exercise “snacks”. These exercises can last anywhere from 20 seconds to two minutes. Then you can have a rest for 30 minutes to four hours before another snack.

It is reported that exercise snacks can be as useful as traditional exercise methods. Just three exercise snacks a day can benefit（使受益）your physical health. Besides that, there are lots of other benefits. Your concentration （专注力）and creativity get better, and you can become more productive. Also, “snacking” throughout the day stops you from sitting too long.

There are so many acceptable exercise snacks, like doing sit-ups, jumping rope or running up and down some stairs（楼梯）. But for those who don’t know where to start, here are some helpful exercise choices:

Exercises such as lifting weights will satisfy the needs. Since most people don’t keep weights at their offices, lift full water bottles.

Squats（深蹲）— moving your body as if to sit down while keeping your back straight. Five to ten of these should make a good snack.

For those who don5t like traditional exercises, simply turn up the music. Pick a lively song and start dancing. It’ll make for a fun workout.

What are you waiting for? Let’s get moving. Your body will thank you for it!

（1）How long can an exercise snack last according to the passage?

A．

20 seconds to two minutes.

B．

30 minutes to four hours.

C．

Five to ten minutes.

（2）Which is an acceptable exercise snack mentioned in the passage?

A．

Doing math exercises.

B．

Eating snacks.

C．

Doing sit-ups.

（3）What is the writer’s attitude（态度）to exercise snacks?

A．

Doubtful.

B．

Unclear.

C．

Supportive.

（4）What is the main purpose of the passage?

A．	To change traditional eating habits.
B．	To introduce an inventive new way to stay fit.
C．	To encourage people to do long-time outdoor exercise.