instruction:
In this task, you're given an article, a question which often contains a blank and four options (associated with "A", "B", "C", "D"). Your task is to find the correct answer (from the given options) for the question from the given article and return one of the options from "A", "B", "C", and "D". Do not generate anything else apart from one of the following characters: "A", "B", "C", "D". There is only one correct answer for each question.
question:
Article: Once I invited a group of friends round to my house, telling them that I was going to record their speech. I said I was interested in their regional accents, and that it would take only a few minutes. Thus, on one evening, three people turned up at my house and were shown into my front room. When they saw the room they were a bit alarmed, for it was laid out as a studio. In front of each easy chair there was a microphone at head height, with wires leading to a tape-recorder in the middle of the floor. I explained that all I wanted was for them to count from one to twenty. Then we could relax and have a drink. I turned on the tape-recorder and each in turn seriously counted from one to twenty in their best accent. When it was over, I turned the tape-recorder off and brought round the drinks, and for the rest of the evening there was general cheerful conversation--interrupted only by the fact that I had to take a telephone call in another room, which unfortunately lasted some time. Or at least that was how it would appear. For, of course, the microphones were not connected to the tape-recorder in the middle of the room at all but to another one, which was turning happily away in the kitchen. The participants, having seen the visible tape-recorder turned off, paid no more attention to the microphones which stayed in front of their chairs, only a few inches from their mouths, thus giving excellent sound quality. And my lengthy absence meant that I was able to obtain as natural a piece of conversation as it would be possible to find. I should add, perhaps, that I did tell my friends what had happened to them, after the event was over, and gave them the choice of destroying the tape. None of them wanted to--though for some years afterwards it always seemed to be my round when it came to the buying of drinks. Linguistic research can be a very expensive business.
Question: The writer asked his friends to count from one to twenty because _ .
Options: (A) he wanted to record the numbers for his research (B) he wanted to find out whether the tape recorder was working (C) he wanted to make his friends relax before real recording started (D) he wanted his friends to think that was all he wanted to record
answer:
D

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Article: Thousands of taxi drivers in Shenyang, Liaoning province, reportedly blocked streets with their vehicles on Sunday in protest against unlicensed vehicles using taxi-hiring apps and apps-based car rental companies providing passenger services, including high-end cars. Although the drivers also complained about the withdrawal of the fuel subsidy by the government, their main complaint was the loss of business because of the rising number of Internet-based car services companies. On Wednesday, news reports came that Beijing transport authorities will take measures to stop the illegal "taxi business" of private cars through the newly rising Internet apps, following the footsteps of Shenyang and Nanjing.[:Z#xx#k.Com] It is not yet clear how the Shenyang city government will handle the issue and whether it will declare the services offered by market leaders such as Didi Dache, a taxi-hiring app provider backed by Tencent Holdings, and Kuaidi Dache illegal. But Shanghai transport regulators have set a rule, by banning Didi Zhuanche, or car services offered by Didi Dache in December. Such regulations will cause a setback to the car-hiring companies and investors that are waiting to cash in on the potentially booming business. Just last month, Didi Dache got $700 million in funding from global investors, including Singapore state investment company Temasek Holdings, Russian investment company DST Global and Tencent. Besides, the market is uncertain that Kuaidi Dache is about to finalize its latest round of funding after getting $800 million from global investors. Regulatory uncertainties, however, could cast a shadow on the future of the Internet-based car-hiring services, which have become popular in most of China's big cities. To be fair, these companies' business model is anything but bad. For example, Didi Zhuanche works side by side with established car rental companies to provide high-end car service mainly for businesspeople through the Internet and mobile phone apps. Every link in this business model chain has legal companies and services. Hence, it is hard to define it as illegal and ban it.
Question: Why did taxi drivers in Shenyang block the streets with their vehicles?
Options: (A) Because they wanted the government to increase their driving allowances. (B) Because they wanted to be educated how to use the taxi-hiring apps. (C) Because they wanted to make their main complaints known to the government. (D) Because they wanted to call on passengers not to hire the private cars.
answer:
C

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Article: Mosquitoes ruin countless American picnics every year, but around the world, this bloodsucking beast isn't just annoying--it causes a health problem. More than a million people die from the spread of mosquito-borne diseases like malaria and yellow fever each year. Attempts to control populations via insecticides like DDT have had ruinous side effects for nature and human health. Neurobiologist Leslie B. Vosshall has a different solution for stopping the insects and the spread of disease. "I believe the key to controlling mosquito behavior is to understand better how they sense us," she says. At their Rockefeller University lab, Vosshall and her colleagues are studying the chemical sensory processes by which mosquitoes choose hosts. How do they sense heat, humidity, carbon dioxide, and body odor ? What makes some people more attractive to a mosquito than others? It takes blood and sweat to find out. To study how mosquitoes assess body odor, Vosshall and her teammates might wear stockings on their arms and keep from showering for 24 hours to create sample smells, _ They insert their arms into the insects' hidden home to study how mosquitoes land, bite, and feed and then they document how this changes. This can mean getting anywhere from one bite to 400, depending on the experiment. Studying male mosquitoes is more pleasant. Since they don't feed on blood, the lab tests their sense of smell using honey. Vosshall and her team have also begun to study how genetics contribute to mosquitoes' choice of a host. She's even created a breed that is unable to sense carbon dioxide, an important trigger for the insects. "By using genetics to make mutant mosquitoes, we can document exactly how and why mosquitoes hunt humans," Vosshall says. Once Vosshall figures out what makes mosquitoes flock to us, she can get to work on making them leave us alone. Many of her lab's proposed solutions sound simple enough, including bracelets that carry long-lasting repellants or traps that can reduce populations, but the breakthroughs, when they come, may save millions of lives in the developing world--and a lot of itching everywhere else.
Question: Vosshall and her colleagues are mainly studying mosquitoes' _ .
Options: (A) appearance (B) size (C) behavior (D) change
answer:
C