In this task, you're given an article and an answer. Your task is to generate the question for the answer based on the given article.

Let me give you an example: Article: There are a lot of public libraries in Britain. These libraries have more than one hundred and fifteen million books, not including those libraries of public schools. Public libraries not only lend books, music records but also help children, patients in hospitals and others to get special play readings, film shows and so on. The first public libraries were founded in about the year 1850. Today's public libraries usually have a reading-room, a lending room and a reference room. The greatest and most famous library in Britain is that of the British Library in London. It was founded in 1973 and has over 10, 000, 000 books. It has nearly every magazine, newspaper and book published in Britain and other parts across the world.
Answer: 10,000,000 or less.
The answer to this example can be: How many books are there in the British Library?
Here is why: In the Article, 10,000,000 is mentioned for the number of books available in the British Library, so this is a good question.

OK. solve this:
Article: For a long time, the traditional method of identifying liars was to watch their body language, including facial expressions. What if the person appears to be nervous? Is the person unable to look me in the eye? Is he or she look around the room? What about other nervous movements, such as fidgeting or shifting from side to side? Many people--from parents to police officers and airport security personnel--depend on this method. But does a person's body and face reveal the truth? Not according to a new study. Talking, it seems, is the best way to smoke out a liar. That is what researchers in the United Kingdom found out recently. Their investigation took place at one place where lying can get you into big trouble--an airport. The researchers asked volunteers to pretend they were real passengers and then lie to airport security agents. Some of the agents used spoke conversation-based methods to question these make-believe passengers. Others depended instead on the person's body language, like lack of eye contact and showing signs of nervousness. The agents talking with the passengers were 20 times more likely to catch the liars. The study found that these conversation-based techniques can help you recognize when a person is lying to you. Like many methods, this conversation method has a name. It is called Controlled Cognitive Engagement or CCE, for short. The British government partly financed this study. The American Psychological (APA) published the findings. Body language cannot be trusted. Using body language and facial expressions to catch someone in a lie is really hard. And it only works, seemingly, by chance. Thomas Ormerod is the head of the School of Psychology at the University of Sussex in England. On the APA website, he reported that the "suspicious-signs method"--or using body language--"almost completely fails" in finding lies.
Answer: Communicate with researchers by talking.
Answer:
What should volunteers in the investigation do?