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.

[EX Q]: Article: China is a land of bicycles. At least it was back in 1992 when I traveled the country. Back then everyone seemed to be riding a bicycle. Millions of them, all black. Cars were rare. Yet since my arrival in Beijing last year, I've found the opposite is true. There are millions of cars. However, people still use their bicycles to get around. For many, it's the easiest and cheapest way to travel today. Bicycles also come in different colors---silver, green, red, blue, yellow, whatever you want. It's fun watching people biking. They rush quickly through crossroads, move skillfully through traffic, and ride even on sidewalks . Bicycles allow people the freedom to move about that cars just can't provide. Eager to be part of this aspect of Chinese culture, I decided to buy a bicycle. Great weather accompanied my great buy. I immediately jumped up on my bicycle seat and started home. My first ride home was orderly . To be safe, I stayed with a "pack" of bikers while cars on the streets came running swiftly out of nowhere at times. I didn't want to get hit. So I took the ride carefully. Crossing the streets was the biggest problem. It was a lot like crossing a major highway back in the United States. The streets here were wide, so crossing took time, skill and a little bit of luck. I finally made it home. The feeling on the bicycle was amazing. The air hitting my face and going through my hair was wonderful. I was sitting on top of the world as I passed by places and people. Biking made me feel alive.
Answer: Because they are convenient and inexpensive.
[EX A]: According to the author, why are bicycles still popular in China today?

[EX Q]: 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.
[EX A]: What should volunteers in the investigation do?

[EX Q]: Article: It's a fact that we all dream. Some dreams seem to last for hours, others only for seconds. Some of us have strange dreams, some have interesting dreams, and some of us have unpleasant dreams. Tests in the 1980s showed that these dreams occur within 90-minute cycles, each cycle made up of six stages. In the last stage people experience rapid eye movement, known as REM, and it is in this stage that dreaming takes place. Eighty percent of people who were woken during this sixth stage could easily remember their dreams. On the other hand, when during the first five stages (NREM), only seven percent could describe a dream. However, of these same people woken during the first five stages, 74% were able to remember thinking activity, although they would not call it a dream. NerysDee, who has written about dreams in a book called "Your Dreams and What They Mean" says: "Perhaps during NREM sleep we are sorting out our outer mundane problems, but in REM sleep we are dealing with inside matters." She also makes the following statement about 90-minute cycle: It may also prove the reason why _ who wake in the middle of the night find it impossible to get to sleep again for at least an hour and a half. In other words, until they have missed out one complete 90-minute sleep period.
Answer: Some people have long dreams and others have very short ones.
[EX A]:
Which of the following statements about dreams is TRUE?