In the future，therapy patients may spend less time sitting in a therapist's office and more time exploring virtual worlds.Researchers have created a new virtual reality（VR）app to treat the fear of heights.The app just had a clinical trial.
   People developed other VR therapies in the past.These programs needed a real-life therapist to guide patients through the treatment.But the new system only uses an animated avatar（虛擬化身）within the app.The avatar coaches patients as they climb a virtual high-rise.This kind of therapist-free counseling could make it much easier for people to get help for fears and other disorders.
   This is "a huge step forward" for VR therapy，says Jennifer Hames，a clinical psychologist."With this system，people don't need to visit a therapist's office to get expert help.They could get help in their regular doctor's office，or even at home.That could be good for people who aren't comfortable with face-to-face therapy，or who can't afford it，" she says.
   To test how effective their app was，F(xiàn)reeman and colleagues recruited（招募）100 adult volunteers，who were moderately to severely afraid of heights.The researchers randomly assigned 49 people to have VR treatment while the other 51 participants got no treatment.Before the experiment began，participants filled out a questionnaire that rated their fear of heights from 16 to 80.They filled out the same questionnaire right after the treatment.Then they did it again two weeks later.
   The scores of patients who got no treatment stayed the same.But people who used the VR app dropped an average of about 25 points on the scale."The results give strong evidence that the new VR program is more helpful than no treatment at all.But it's not clear how well this type of system could work for more complex mental health issues，" says Mark Hayward，a clinical psychologist at the University of Sussex."And when it comes to helping people with more severe symptoms，VR probably won't replace trained therapists any time soon."

（1）What is the passage mainly about？

C

C

A．The causes of the fear of heights.
B．The results of the fear of heights.
C．A VR app to treat the fear of heights.
D．The treatment of the fear of heights.
（2）What do we know about the VR therapy？

B

B

A．It has a therapist to guide patients.
B．It is convenient and doesn't cost much.
C．It allows patients to climb a real high-rise.
D．It requires patients to go to the therapist's office.
（3）Why did Freeman's team conduct the experiment？

B

B

A．To rate the participants' fear of heights.
B．To check the effectiveness of the VR app.
C．To find out how severe people's fear of heights.
D．To explore a new way to improve the treatment.
（4）In helping people with more severe symptoms，

C

C

.
A．the VR app is very helpful
B．the results of the app are not clear
C．trained therapists are still needed
D．no trained therapists are necessary