Question 3 is based on the news report you have just heard.

News Report Two

听力原文

    Staff at a suburban supermarket in Melbourne say they feel unsafe at work after security guards were removed. This came after a series of physical attacks and verbal abuse by customers. 

    (3) [More than 50 workers at the store have signed a letter calling for a permanent security guard following a series of incidents], including a customer threatening to attack a supervisor with a knife.

    A security worker had guarded the store each night from 7 p.m. until 12 a.m., but that stopped suddenly on Monday, employees said.

    One worker said an angry customer had thrown a chicken at his head after complaining about how long she had waited to be served. Another worker said the lack of protection at the store made her feel uncomfortable at work. (4) [However, the spokesman of the supermarket said the store had taken strong action in response to incidents.] “We have found very few instances of bad customer behavior at our store in the past year. In the rare cases we have seen bad behavior, we have taken strong action in response, including banning a customer from the store.”

3. For what purpose did the staff at a supermarket in Melbourne sign a letter?

解析：D。四个选项均是以不定式动词短语开头，推测问题可能会问某事的目的、意图等。根据录音开头可知，该商店的50多名员工签署了一封公开信，要求雇佣一名固定的安保人员。D项中的call for a permanent security guard为原词复现，故正确答案为D。

错项排除：A项中的high wages和B项中的health care在录音中均未提及，故排除。录音中提到了supervisor（主管）一词，但录音中说的是一名顾客威胁要用刀袭击主管的事件，并没有说到主管脾气不好或要将其解雇，故C项错误。