C

　　The problem of robocalls has gotten so bad that many people now refuse to pick up calls from numbers they don’t know. By next year, half of the calls we receive will be scams(欺诈). We are finally waking up to the severity of the problem by supporting and developing a group of tools, apps and approaches intended to prevent scammers from getting through. Unfortunately, it’s too little, too late. By the time these "solutions"(解决方案)become widely available, scammers will have moved onto cleverer means. In the near future, it’s not just going to be the number you see on your screen that will be in doubt. Soon you will also question whether the voice you’re hearing is actually real.

　　That’s because there are a number of powerful voice manipulation ( 处理 ) and automation technologies that are about to become widely available for anyone to use. At this year’s I/O Conference, a company showed a new voice technology able to produce such a convincing human-sounding voice that it was able to speak to a receptionist and book a reservation without detection.

　　These developments are likely to make our current problems with robocalls much worse. The reason that robocalls are a headache has less to do with amount than precision. A decade of data breaches(数据侵入)of personal information has led to a situation where scammers can easily learn your mother’s name, and far more. Armed with this knowledge, they’re able to carry out individually targeted campaigns to cheat people. This means, for example, that a scammer could call you from what looks to be a familiar number and talk to you using a voice that sounds exactly like your bank teller’s, tricking you into "confirming" your address, mother’s name, and card number. Scammers follow money, so companies will be the worst hit. A lot of business is still done over the phone, and much of it is based on trust and existing relationships. Voice manipulation technologies may weaken that gradually.

　　We need to deal with the insecure nature of our telecom networks. Phone carriers and consumers need to work together to find ways of determining and communicating what is real. That might mean either developing a uniform way to mark videos and images, showing when and who they were made by, or abandoning phone calls altogether and moving towards data-based communications — using apps like FaceTime or WhatsApp, which can be tied to your identity.

　　Credibility is hard to earn but easy to lose, and the problem is only going to get harder from here on out.

　　38. How does the author feel about the solutions to problem of robocalls?

　　A. Panicked. B. Confused. C. Embarrassed. D. Disappointed.

　　39. Taking advantage of the new technologies, scammers can ___________.

　　A. aim at victims precisely B. damage databases easily

　　C. start campaigns rapidly D. spread information widely

　　40. What does the passage imply?

　　A. Honesty is the best policy.

　　B. Technologies can be double-edged.

　　C. There are more solutions than problems.

　　D. Credibility holds the key to development.

　　41. Which of the following would be the best title for the passage?

　　A. Where the Problem of Robocalls Is Rooted

　　B. Who Is to Blame for the Problem of Robocalls

　　C. Why Robocalls Are About to Get More Dangerous

　　D. How Robocalls Are Affecting the World of Technology

　　D

　　By the end of the century, if not sooner, the world’s oceans will be bluer and greener thanks to a warming climate, according to a new study.

　　At the heart of the phenomenon lie tiny marine microorganisms(海洋微生物)called phytoplankton. Because of the way light reflects off the organisms, these phytoplankton create colourful patterns at the ocean surface. Ocean colour varies from green to blue, depending on the type and concentration of phytoplankton. Climate change will fuel the growth of phytoplankton in some areas, while reducing it in other spots, leading to changes in the ocean’s appearance.

　　Phytoplankton live at the ocean surface, where they pull carbon dioxide(二氧化碳)into the ocean while giving off oxygen. When these organisms die, they bury carbon in the deep ocean, an important process that helps to regulate the global climate. But phytoplankton are vulnerable to the ocean’s warming trend. Warming changes key characteristics of the ocean and can affect phytoplankton growth, since they need not only sunlight and carbon dioxide to grow, but also nutrients.

　　Stephanie Dutkiewicz, a scientist in MIT’s Center for Global Change Science, built a climate model that projects changes to the oceans throughout the century. In a world that warms up by 3℃, it found that multiple changes to the colour of the oceans would occur. The model projects that currently blue areas with little phytoplankton could become even bluer. But in some waters, such as those of the Arctic, a warming will make conditions riper for phytoplankton, and these areas will turn greener. "Not only are the quantities of phytoplankton in the ocean changing,"she said, "but the type of phytoplankton is changing. "

　　And why does that matter? Phytoplankton are the base of the food web. If certain kinds begin to disappear from the ocean, Dutkiewicz said, "it will change the type of fish that will be able to survive." Those kinds of changes could affect the food chain.

　　Whatever colour changes the ocean experiences in the coming decades will probably be too gradual and unnoticeable, but they could mean significant changes. "It’ll be a while before we can statistically show that the changes are happening because of climate change," Dutkiewicz said, "but the change in the colour of the ocean will be one of the early warning signals that we really have changed our planet."

　　42. What are the first two paragraphs mainly about?

　　A. The various patterns at the ocean surface.

　　B. The cause of the changes in ocean colour.

　　C. The way light reflects off marine organisms.

　　D. The efforts to fuel the growth of phytoplankton.

　　43. What does the underlined word"vulnerable"in Paragraph 3 probably mean?

　　A. Sensitive. B. Beneficial. C. Significant. D. Unnoticeable.

　　44. What can we learn from the passage?

　　A. Phytoplankton play a declining role in the marine ecosystem.

　　B. Dutkiewicz’s model aims to project phytoplankton changes.

　　C. Phytoplankton have been used to control global climate.

　　D. Oceans with more phytoplankton may appear greener.

　　45. What is the main purpose of the passage?

　　A. To assess the consequences of ocean colour changes.

　　B. To analyse the composition of the ocean food chain.

　　C. To explain the effects of climate change on oceans.

　　D. To introduce a new method to study phytoplankton.