You will hear an interview with Tom Edison about U.S. technology formation.

You will hear an interview with Tom Edison about U.S. technology formation.
For each question(23-30), mark one letter(A, B or C)for the correct answer.
After you have listened once, replay the recording.
You have 45 seconds to read through the questions.
[Pause]
Now listen, and mark A, B or C.
Woman: Chinese and Indian scientists and engineers have made an unexpectedly large contribution to U.S. technology formation over the last 30 years, according to a new research by Tom Edison. But that trend may be ebbing, with potentially harmful effects on future growth in American innovation. Mr. Edison is here with us.
Man: Grace, it’s great to be here.
Woman: What led to your interest in this area?
Man: In the late 1990s, I worked with a large Korean chaebol, a South Korean business conglomerate, on a spin-off venture to commercialize a wireless telecom technology invented by a Korean entrepreneur living in Silicon Valley. I was impressed during this project with both the importance of foreign-born scientists and entrepreneurs for U.S. technology formation, and the close ties that some of these expatriates maintained with their home countries.
Woman: For the Korean inventor, his home country was clearly his default choice when looking for a partner.
Man: Right. As Silicon Valley is a special place on many dimensions, I sought to characterize how well this case study was generalized to other cities, industries, and ethnic groups.
Woman: Your study used a unique name-matching technique to identify ethnic patterns. Why did you choose this method?
Man: This project employs the names on U.S. patents to determine probable ethnicities of the inventors. For example, inventors with the surnames Wang and Ming are more likely Chinese than Hispanic.
Woman: What trends did your findings reveal?
Man: The most striking trend is the strong growth in Chinese inventors’ contributions to U.S. innovation building from under 2 percent of U.S. domestic inventors in 1975 to over 8 percent today. Indian inventors also rise dramatically during this 30-year period, to almost 5 percent in 2000, before slightly declining thereafter. During this period, English and European contributions have declined somewhat in magnitude.
Woman: Is there a direct or indirect impact on the U.S. workforce or economy?
Man: Immigrants are a strong force for U.S. technology development through their quantity and quality.
They account for nearly 50 percent of our science and engineering doctorates, while being just over 10 percent of the overall U.S. workforce.
Woman: In terms of quality, immigrants have made exceptional contributions at the very top, for example, in terms of Nobel Prize.
Man: These contributions are an overall advantage to U.S. innovation, but more research is required to characterize the details and mechanisms, including important issues such as the impact for native scientists and engineers.
Woman: Which industries are the patents focusing on? Are they concentrating on a specific industry or a business type?
Man: Inventors can file for patents in many technology fields, ranging from chemicals and drugs to computer software and agricultural machinery. Immigrant contributions are especially strong in high-tech fields compared with more traditional applications like mechanical patents.
Woman: Your data shows the ethnic composition of U.S. scientists and engineers undergo a significant transformation, with contributions of Chinese and Indian scientists to U.S. technology formation leveling off after 2000 and, in the case of India, declining. What accounts for this trend, and what are the potential ramifications for U.S. technology formation in the future?
Man: Explaining these trends and their long-term implications will be a central theme of my future research. A couple of factors are likely to play important roles. The first is recent U.S. immigration restrictions following 9.11 which resuets in the reduction in the number of H1-B visas available for temporary, high-skilled workers. Secondly, both India and China have become more attractive places for technology development and entrepreneurship, leading to less initial migration to the United States and greater returning migration.
Woman: Any other factors?
Man: Yes, more explanations may also exist. For example, stronger relative growth of innovation in technology fields did not employ as many Chinese or Indian inventors.
Woman: What’s your forecast on this trend?
Man: Only with a complete characterization of these mechanisms can we begin to forecast future implications with accuracy. We can nevertheless agree that attracting and retaining these ethnic researchers is an important facet for maintaining U.S. technology leadership, and recent trends may be a warning flag.