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.

Article: Ladybirds didn't have black spots on their backs at first. Then a storm broke out, and their famous guide, Caius Insectus, disappeared into the flood , and the few ladybirds who survived had to choose a new leader to guide them out of trouble. They decided that their new leader would be the first ladybird to successfully travel south to the Great Lake and return to describe it. Many young ladybirds moved off immediately into this adventure. One by one they returned and told of how beautiful the southern lake was at that time of year, with its clear waters and flowers. However, the last of the ladybirds was late in getting back. He hadn't managed to reach the lake. Everyone criticized him, and they prepared to continue their journey the next day. Following their new guide, they spent a morning walking northwards until they reached some tall thick grassland, where they stopped. There were no clear waters or flowers in front of them. The heavy rain had turned the place into a huge green puddle . Everyone understood what had happened. When the ladybirds had gone out looking for the lake, they had gone in the wrong direction. Now they could see that, except that one late ladybird, they had lied in order to get what they wanted. And so, the late little ladybird was made the Great Guide. They also decided that every time one of them was discovered lying they would paint a black spot on that ladybird's back. From then on, when a ladybird looks at another's back, it can tell whether that ladybird can be trusted.
Question: Why did the ladybirds decide to choose a new guide?
Options: (A) They lost their way in the storm. (B) They weren't satisfied with Caius Insectus. (C) They needed someone to lead them out of danger. (D) They needed someone to help prepare for the storm.
C

Article: Australian scientists say an organic compound used by Indian women to paint dots or bindi on their foreheads could hold the key to a breakthrough in cancer treatment. Rose Bengal was first used in the early 1900s as a dye for food, textiles and cosmetics. But now it is proving to be a useful weapon in the fight against skin cancer. Television advertisements constantly warn of the dangers of overexposure to the fierce sun. Among them is the possibility of the disease melanoma , a type of skin cancer. More than 1,200 Australians die every year from the disease. Initial trials of a solution of Rose Bengal injected into some melanoma cells have had a 75 percent success rate in controlling the disease. Professor John Thompson, the director of the Melanoma Unit at the University of Sydney, says this organic dye could become a powerful cancer-fighting treatment. "We believe it works by getting into the tumor cells and causing them to self-destruct. But the exact mechanism by which it works is not totally clear. It's not useful for people who have a primary melanoma. The treatment of primary melanoma is surgical excision ,"he said. "It's useful to inject tumors for people who have recurrences; when the primary treatment has failed and when recurrence in the area, or at more distant sites has occurred." About 90 percent of Australians who develop melanoma survive thanks to early diagnosis and treatment. If left untreated, however, the disease can be fatal. Convincing younger people in Australia about the dangers of overexposure to the sun is a battle campaigners are constantly waging. Veronica Manock, a 21-year-old student, had two major operations to remove a cancerous tumor from her leg. "I've had a lot of friends who just said 'I thought it was just, you know, I'll get a mole cut out and that's it', whereas I don't think people realize how much danger they're putting themselves into and how easy it is to stop something like this happening to you just from doing little things,"said Marock. Other researchers in Australia are investigating genetic treatments to skin cancer. There is a pressing need for such research to produce effective treatments. Australians, the majority of whom are fair-skinned , are four times more likely to develop a melanoma than people in Canada, the United States or Great Britain.
Question: The information about Rose Bengal is wrong EXCEPT that _ .
Options: (A) it is no longer used as a dye (B) it is used to cure skin cancer (C) it is a special kind of rose planted in Australia (D) it can be effective in treating skin cancer
D

Article: Anyone driving the twists of Highway 1 between San Francisco and Los Angeles recently may have glimpsed a Toyota Prius car with a curious-looking thing on the roof. Harder to notice was that the person at the wheel was not actually driving. The car is a project of Google, which has been working in secret but in plain view( anyhow, no one can keep such a thing from the public) on vehicles that can drive themselves, using artificial-intelligence software that can sense anything near the car and imitate the decisions made by a human driver. With someone behind the wheel to take control if something goes wrong and a technician in the passenger seat to monitor the navigation system , seven test cars have driven 1,000 miles without human intervention and more than 140,000 miles with only occasional human control. One even drove itself down Lombard Street in San Francisco, one of the steepest and curviest streets in the nation. The only accident, engineers said, was that one Google car was rear-ended when it stopped at a traffic light. Autonomous cars are years from mass production, but technologists who have long dreamed of them believe that they can transform society as profoundly as the Internet has. Robot drivers react faster than humans, have 360-degree perception and do not get distracted or sleepy, the engineers argue. They speak in terms of lives that could be saved and injuries that could be avoided--- more than 37,000 people died in car accidents in the United States in 2008. The engineers say the technology could double the capacity of roads by allowing cars to drive more safely while closer together. Because the robot cars would eventually be less likely to crash, they could be built lighter, reducing fuel consumption. But of course, to be truly safer, the cars must be far more reliable than, say, today's personal computers, which crash on occasion and are frequently infected. The Google research program using artificial intelligence to revolutionize the automobile is proof that the company's ambitions reach beyond the search engine business. The program is also a departure from the mainstream of innovation in Silicon Valley, which has turned toward social networks and Hollywood-style digital media. However, the Google researchers said the company did not yet have a clear plan to create a business from the experiments.
Question: What can we learn from the passage?
Options: (A) Only seven autonomous cars have been created so far. (B) Nobody in the car took control during the 140,000miles trip. (C) It will take a long time before the autonomous car is put into the market. (D) When driving on the Lombard Street, all test cars broke down.
C