DESERTS CHOOSE THE WORD WHOSE UNDERLINED PART IS PRONOUNCED DIFFERENT...

45. According to the passage, which of the following is the most important cause of

desertification?

A. The change of climate

B. The spread of deserts

C. Human activities

D. Cattle destroying trees

Choose the word or phrase (A, B, C, or D) that best fits each space in the following passage.

DESERTIFICATION

The Sahara Desert is growing by 10kms each year. The whole earth gets 600km

²

of desert

area more every year. This process is called "desertification". This term started being (46)_____

in the 1950s.

The idea of desertification was first known in the 1930s. Much of the Great Plains grew

very dry (47)______ a result of drought and poor farming techniques. It was called the Dust

Bowl. Millions were forced to leave their farms and their ways of life. Since then, (48)_____

have been great improvements in farming practices in the Great Plains. These have prevented the

Dust Bowl disaster (49)______ again.

Grazing is one worry. Cows do two things to the soil. First, they eat grasses and plants that

hold the soil in place. Second, their hooves break down the top layer of soil. The result is that the

good soil can be blown away by the wind. The dirt (50)______ behind is not good for growing.