Read the following article and select the best answer. Article: Boris Worm of Dalhousie University in Nova Scotia ,prefix = st1 /Canada, led the international team that did the study . Professor Worm says species have recently been disappearing from oceans at increasing speed . At this rate , he says , all seafood species could collapse could collapse by 2048 . Other studies have also warned about the dangers of overfishing and the effects on ocean environments . But not everyone thinks the oceans are likely to be empty in fifty tears . Some scientists said parts of the world do have problems , but others are doing a good job of protecting fish populations . Government officals in several countries with large fishing industries also questioned the research . The study appeared earlier this month in Science magazine . The researchers say damage to oceans affects not only fish populations but also the productivity of ecosystems . These complex systems help control water quality . The scientists say the loss of different kinds of sea life appeared to increase the f fish kills and beach closures from harmful algae growth . The scientist examined the results of thirty-two experiments and observed forty-eight protected areas . They also looked at records of catches worldwide . They studied records from the United Nations Food and Agriculture Organization from nineteen fifty to two thousand three . And they examined archeological information and other historical records for twelve coastal areas . That research back over a thousand years . Boris Worm says the findings were , in his words , " beyond anything we suspected . " But he also said the situation is not too late to correct . He said that with good fisheries management , some species could completely recover in three to ten years . Question: The conclusion of the research led by Boris Worm is _ . - unbearable - unbelievable - doubtful - convincing
convincing

Read the following article and select the best answer. Article: For well over a thousand years, smallpox was a disease that everyone feared. The disease killed much of the native population in South America when the Spanish arrived there in the early sixteenth century. By the end of the eighteenth century, smallpox was responsible for about one in ten deaths around the world. Those who survived the disease were left with ugly scars on their skin. It had long been well known among farmers that people who worked with cows seldom caught smallpox; instead, they often caught a similar but much milder disease called cowpox . A British doctor called Jenner was extremely interested in this, and so he studied cowpox. He believed that, by vaccinating people with the disease, he could protect them against the much worse disease smallpox. In 1796, he vaccinated a boy with cowpox and, two months later, with smallpox. The boy did not get smallpox. In the next two years, Jenner vaccinated several children in the same way, and none of them got the disease. News of the success of Jenner's work soon spread. Vaccination soon became a common method to protect people against other diseases caused by virus, such as rabies , and vaccines were sent across the world to the United States and India. It took nearly two centuries to achieve Jenner's dream of getting free of smallpox from the whole world. In 1967, the world Health Organization (WHO) started a great vaccination program, and the last known case of smallpox was recorded in Somalia in 1977. The story of vaccinations does not end there, however. There are many other diseases that kill more and more people every year. Besides, many new diseases are being discovered. The challenge for medical researchers will, therefore, probably continue for several more centuries Question: Smallpox was so serious that _ by the end of l8th century - its death rate was up to ten percent - those who caught it were certain to die - one in ten people in the world died of smallpox - one in ten deaths in the world was caused by smallpox
one in ten deaths in the world was caused by smallpox

(Q).
Read the following article and select the best answer. Article: Some years ago,writing in my diary used to be a usual activity.I would return from school and spend the expected half hour recording the day's events,feelings,and impressions in my little blue diary.I did not really need to express my emotions by way of words,but I gained a certain satisfaction from seeing my experiences forever recorded on paper.After all,isn't accumulating memories a way of preserving the past? When I was thirteen years old,I went on a long journey on foot in a great valley,wellequipped with pens,a diary,and a camera.During the trip,I was busy recording every incident,name and place I came across.I felt proud to be spending my time productively,dutifully preserving for future generations a detailed description of my travels.On my last night there,I wandered out of my tent,diary in hand.The sky was clear and lit by the glare of the moon,and the walls of the valley looked threatening behind their screen of shadows.I automatically took out my pen... At that point,I understood that nothing I wrote could ever match or replace the few seconds I allowed myself to experience the dramatic beauty of the valley.All I remembered of the previous few days were the dull characterizations I had set down in my diary. Now,I only write in my diary when I need to write down a special thought or feeling.I still love to record ideas and quotations that strike me in books,or observations that are particularly meaningful.I take pictures,but not very often-only of objects I find really beautiful.I'm no longer blindly satisfied with having something to remember when I grow old.I realize that life will simply pass me by if I stay behind the camera,busy preserving the present so as to live it in the future. I don't want to wake up one day and have nothing but a pile of pictures and notes.Maybe I won't have as many exact representations of people and places;maybe I'll forget certain facts,but at least the experiences will always remain inside me.I don't live to make memories-I just live,and the memories form themselves. Question: Before the age of thirteen,the author regarded keeping a diary as a way of _ . - observing her school routine - expressing her satisfaction - impressing her classmates - preserving her history
(A).
preserving her history