Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer for each of the following questions.

There are deserts all over the world. They can be found in Africa, China, South America, and North America. In some places, deserts are growing. This is a serious problem because deserts destroy farmland and ruin the land where animals live. When people cannot grow food or find animals to eat, they have to leave their homes.
Sometimes, nature can cause deserts to spread. Wind can move sand away from deserts and onto useful land. When there is no rain for a long time, plants die and deserts grow. However, humans can also cause deserts to grow. This is called desertification, and it happens in many ways. One way is when people cause too much air pollution, which can make an area hotter. Hotter weather can reduce the amount of rain as well. Too many people in one area can also damage the land. In addition, having many animals can harm the land. When large animals like cows walk on soil too much, they turn it into dust. The wind easily blows this dust away. Trees help hold water in the ground. When people cut down too many trees, less water stays in the ground, and the soil is ruined.
All of these things can speed up desertification. To stop deserts from growing, people must think of ways to treat the land better.

A computer is a wonderful machine. It (6) the most important invention in our modern time. Computers have had a great effect on science, industry, business, machine, and education. Soon it will touch the lives of everyone, even people in distant villages. It is a revolutionary invention. Imagine that you go (7) study English at a college where the local newspaper rarely has news about your home town, but this does not bother you at all. You can sit comfortably in your room, turn on your (8) computer, and search for the news you want on the Internet. The screen is immediately filled with news from all over the world.
Computers can do all kinds of work. When someone buys something in a department (9) , a clerk puts information about the sale into a computer. During the night, the computer system works on the information from all the sales that day. (10) the morning the manager can print out a report on everything that was sold and also on everything that must be reordered.