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: While English is getting more important in our schools, Chinese has become popular among foreign kids. But Chinese can be more difficult to learn. At least 16-year-old Piao Chenglong thinks so. "English is easier for me. Chinese characters have too many strokes ," said Piao. "But I want to learn it. I want to study at Peking University when I grow up." Piao is from South Korea. He came to China in 2008. In South Korea, there are more than 300000 Chinese learners like Piao. Some South Korean students begin to learn to write the language on their first day at school. To help students learn Chinese, South Korea holds speaking competitions for high school students every year. Chinese isn't just popular in South Korea. People from all the world want to learn it. The Chinese Ministry of Education says that nearly 130 million people from 85 countries are learning Chinese. This number will be increasing to 800 million in the coming years. In America, Chinese is the second most popular foreign language after Spanish. Some American middle schools have Chinese classes. Students learn to make jiaozi and tie Chinese knots . Some even try to write and draw in Chinese way! People want to learn Chinese because China is becoming such an important country. Foreign countries want to understand China better to help them with business. The Chinese government is also helping the world learn Chinese. It has sent more than 200 Chinese teachers to more than 60 countries in the world. Many more Confucious College will be set up in the world. These colleges will teach Chinese to foreign students.
Question: Which of the following is the topic sentence for the text?
Options: (A) Chinese has become popular among foreign kids. (B) Chinese can be more difficult to learn. (C) In America, Chinese is the second most popular foreign language after Spanish. (D) Students learn to make jiaozi and tie Chinese knots.
A

Article: As part of an effort to improve treatments for life-threatening illnesses, a team of scientists have created rabbits that glow in the dark. The efforts have produced two rabbits out of a litter of eight that went from being a normal, soft white to glowing green in the dark. The rabbits were born at the University of Istanbul as part of the cooperation between scientists from universities in Turkey and Hawaii. The rabbits glow to show that a genetic operation technique can work efficiently. "The green is not important at all--it's just a marker to show the experiment can be done successfully," said University of Hawaii associate professor, Stefan Moisyadi. To produce the glowing effect, researchers injected jellyfish DNA into a mother rabbit's embryos. Then those embryos were put into the mother. Similar experiments have resulted in glowing cockroaches and cats. Eventually, the researchers hope the technique can lead to new ways to produce medicines, Moisyadi said. "The final goal is to develop animals that are able to produce beneficial molecules in their milk that can be cheaply extracted , especially in countries that cannot afford big factories that make drugs, which usually cost US$1bn to build. Then they will be able to produce their own protein-based medication in animals," Moisyadi said. The rabbits are expected to live as long as non-glowing rabbits, but Moisyadi said he understands people can object to this kind of experimentation involving live animals. "To the people against, I say: think, what are the benefits and what is the harm?" Moisyadi said. "And if the benefits outweigh the harm, let's go with the benefits." Moisyadi started developing the project in 2006, and researchers are now waiting to see if pregnant sheep produce similar results.
Question: What do we know about the glowing rabbits?
Options: (A) Their fur became green after the experiment. (B) They were chosen from a special species of rabbits. (C) The color1 that they glow isn't of interest to scientists. (D) They live shorter lives than ordinary rabbits.
C

Article: Are you carrying too much on your back to school? I'm sure lots of your age will say "Yes". Not only the students in China have this problem, but children in the United States also have heavy school bags. Doctors are starting to worry about that younger and younger students are having problems as a result of school bags being too heavy for them. "It's hard for me to go upstairs with my bag because it's so heavy," said Rich Hammond, an 11-year-old student in the US. Rich is among students who have common school bags with two straps to carry them, but many other choose rolling bags. But even with rolling bags, getting up stairs and houses is still a problem for children. Many of them have hurt backs and necks because of the heavy school bags. But how much is too much? Doctors say students should carry no more than 10% to 15% of their own body weight. Scott Bautch, a black doctor, said children under Grade 4 should stay with 10%. But it is also important that older children don't stay with over 15%, because their bodies are still growing. "Children are losing their balance and falling down with their school bags," he said. Parents and teachers are starting to tell children to only take home library books that they will be reading at night. Some teachers are using pieces of paper or thin workbooks for students to take home. One of the best answers is, as some children said, to have no homework at all.
Question: From the passage we can learn that _ .
Options: (A) only children in China carry too heavy school bags (B) children in other countries don't carry too heavy school bags (C) both children in China and the US carry too heavy school bags (D) only children in the US carry too heavy school bags
C