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: Testing new drugs for safety and effectiveness is a costly process in the United States. It also can take:lot of time. Some scientists are now designing silicon computer chips that act like human organs. The scientists think they have found a way to make the process faster and more economical. The silicon computer chips are smaller than a child's hand. Each one has living cells that act and react like a human organ. The chips are being created as part of a program to test the safety of drug compounds. It is called the Tissue Chip for Drug Screening Program. It is a project of the US National Center for Advancing Tmnslational Sciences, or NCATS. Danilo Tagle is the center's Associate Director. He says a three-dimensional computer chip can be designed to act like a human lung. Some computer chips contain very small models of the human digestive system. They copy the real function or duties of the human stomach and intestine , moving when breaking down food. Drugs are added to the tiny organs for testing through instruments known as micro-tubes. Experiments with the tissue chips have produced more detailed information than tests using animal or cell models. NCATS just announced$17 million in grants to develop an entire human organ system over the next three years.
Question: Why are scientists designing silicon computer chips acting like human organs?
Options: (A) To treat the patients whose body organs don't work well. (B) To examine the health condition of human organs. (C) To make testing new drugs faster and cheaper. (D) .To further study the function of human organs.
C

Article: Can you imagine exchanging the pleasure of city life for a quiet life in the countryside? Many people want to move from the country to the city because they think that life in the city is more exciting and better than that in countryside, especially young people who like new, modern things. People like popular things and feel that they can only find the latest styles in the city. However, it is possible to enjoy the higher quality of country life and still enjoy some of the advantages of living in the city. Nowadays, traveling is fast and easy, and information can be found on the Internet, so many people are able to do their work in home offices. Because they have e-mail and personal computers, they don't have to be in big cities to manage their businesses. It is not important where they actually work because the results of their work can be sent everywhere with e-mails. Therefore, there is no need to put up with all of the disadvantages of the city. Now they can escape busy city life to enjoy the quiet country life and still be able to have successful jobs. Other people are interested in technological things and high-tech jobs and think they can only find them in big cities. If they want to find a job, especially a good position in a company, they think that they have to live in a city. For these jobs, they are willing to put up with many of the disadvantages of city life, such as crime, heavy traffic, and pollution.
Question: The main idea of this passage is that _ .
Options: (A) life in the city is different from life in the countryside (B) people prefer living in the city to living in the countryside (C) cities have more disadvantages than the countryside (D) more and more people like living in the city
A

Article: After the coming of Europeans to the Americas, Indians were forced to change their way of life. Yet the influence of Native American culture is still felt throughout the United States. Many of the foods commonly eaten in the United States today were first grown by American Indians. Among these foods are corn, white and sweet potatoes, peanuts, pumpkins, tomatoes, and certain beans and berries. Native Americans also discovered ways to use herbs and other plants as medicines. Native American inventions, such as canoes, ponchos and parkas ,hammocks and snowshoes are still in use today. Other marks of Indian culture were left in American place names. The state of Alaska, for example, takes its name from a Native American word meaning "great land". Today nearly 1.5 million Native Americans live in the United States. Some still preserve the ways of their ancestors, speaking Indian languages and keeping alive their legends, art forms, and customs. Other Native Americans keep few of the old ways, but remain proud of their people's contributions to American history. Americans have come to appreciate the beauty of Indian crafts . Many artists find _ in traditional Indian designs. Many Indian values, too, have become widely held. Americans today believe that the land, air and water are precious resources that must be carefully protected. As one government official wrote recently: We have slowly come back to some of the truths that the Indians knew from the beginning. People need to learn from nature, to keep an ear to the earth, and to refill their spirits in frequent contacts with animals and wild land.
Question: What does "Native Americans" refer to in the passage?
Options: (A) Europeans settling in the Americas. (B) People born and living in America. (C) American Indians. (D) Americans.
C