Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

His work ________ new ground in the treatment of cancer. It is now giving many cancer victims hope of complete recovery.         
A.broke                      
B.found                      
C.dug                                                 
D.uncovered

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Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.
            Overpopulation, the situation of having large numbers of people with too few resources and too little space, is closely associated with poverty. It can result from high population density, or from low amounts of resources, or from both. Excessively high population densities put stress on available resources. Only a certain number of people can be supported on a given area of land, and that number depends on how much food and other resources the land can provide. In countries where people live primarily by means of simple farming, gardening, herding, hunting, and gathering, even large areas of land can support only small numbers of people because these labor-intensive subsistence activities produce only small amounts of food.
            In developed countries such as the United States, Japan, and the countries of Western Europe, overpopulation generally is not considered a major cause of poverty. These countries produce large quantities of food through mechanized farming, which depends on commercial fertilizers, large-scale irrigation, and agricultural machinery. This form of production provides enough food to support the high densities of people in metropolitan areas. 
            A country’s level of poverty can depend greatly on its mix of population density and agricultural productivity. Bangladesh, for example, has one of the world’s highest population densities, with 1,147 persons per sq km. A large majority of the people of Bangladesh engage in low-productivity manual farming, which contributes to the country’s extremely high level of poverty. Some of the smaller countries in Western Europe, such as the Netherlands and Belgium, have high population densities as well. These countries practice mechanized farming and are involved in high-tech industries, however, and therefore have high standards of living.
            At the other end of the spectrum, many countries in sub-Saharan Africa have population densities of less than 30 persons per sq km. Many people in these countries practice manual subsistence farming; these countries also have infertile land, and lack the economic resources and technology to boost productivity. As a consequence, these nations are very poor. The United States has both relatively low population density and high agricultural productivity; it is one of the world’s wealthiest nations.
            High birth rates contribute to overpopulation in many developing countries. Children are assets to many poor families because they provide labor, usually for farming. Cultural norms in traditionally rural societies commonly sanction the value of large families. Also, the governments of developing countries often provide little or no support, financial or political, for family planning; even people who wish to keep their families small have difficulty doing so. For all these reasons, developing countries tend to have high rates of population growth.
The word “infertile” in paragraph 4 probably means ______.
A.inaccessible                  
B.unproductive                  
C.impossible             
D.disused

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.
            One of the seven wonders of the ancient world, the Great Pyramid of Giza was a monument of wisdom and prophecy built as a tomb for Pharaoh Cheops in 2720 B.C. Despite its antiquity, certain aspects of its construction makes it one of the truly wonders of the world. The thirteen- acre structure near the Nile river is a solid mass of stone blocks covered with limestone. Inside are the number of hidden passageways and the burial chamber of the Pharaoh. It is the largest single structure in the world. The four sides of the pyramid are aligned almost exactly on true north, south, east and west-an incredible engineering feat. The ancient Egyptians were sun worshippers and great astronomers, so computations for the Great Pyramid were based on astronomical observations.
            Explorations and detailed examinations of the base of the structure reveal many intersecting lines. Further scientific study indicates that these represent a type of timeline of events – past, present and future. Many of the events have been interpreted and found to coincide with known facts of the past. Others are prophesied for future generations and are currently under investigation. Many believe that pyramids have supernatural powers and this one is no exception. Some researchers even associate it with extraterrestrial beings of ancient past.
            Was this superstructure made by ordinary beings, or one built by a race far superior to any known today?
What was the most probable reason for providing so many hidden passages?
A.To allow the weight of the pyramid to settle evenly.    
B.To permit the high priests to pray at night.
C.To keep grave robbers from finding the tomb and the treasure buried with the Pharaoh.
D.To enable the Pharaoh’s family to bring food for his journey to the afterlife