题目内容：

    Taking your pulse during physical activity allows you to measure how hard you are exercising. You should exercise to stay within your target heart range.

Increasing your heart rate is a key part of exercise, but it is important that your heart rate is not too high or too low. If you are a beginner, you should also be able to breathe comfortably while exercising. This will ensure that you are exercising at a level that is safe and effective for your body.

The chart below illustrates target heart rate ranges for exercise based on the maximal heart rate for selected ages. Here are the steps for using the chart:

1.Which of the following is TRUE?

A.Exercise intensity can be reflected by a person’s heart rate.

B.The faster your heart rate is, the more effective the exercise is.

C.Vigorous exercise will definitely present a threat to people’s safety.

D.The target exercise heart rate range for a 45-year-old is 90–149 BPM.

2.A 34-year-old man is running and the number of pulses he takes for 15 seconds is 40.

His fitness coach had better tell him _____________.

A.“You are doing fine.” B.“You can run faster.”

C.“You should slow down a bit.” D.“You should drink some water.”

3.What is the purpose of this passage?

A.To advise people to form a habit of taking their pulses while exercising.

B.To inform people of the target heart rate zone for those aged 60 and under.

C.To tell people the importance of maintaining moderate amount of exercise.

D.To show people how to measure heart rate to keep proper exercise intensity.