[单项选择]

Text 4
Although, recent years have seen substantial reductions in noxious pollutants from individual motor vehicles, the number of such vehicles has been steadily increasing. Consequently, more than 100 cities in the U. S. still have levels of carbon monoxide, particulate matter, and ozone that exceed legally established limits. There is a growing realization that the only effective way to achieve further reduction in vehicle emissions—short of a massive shift away from the private automobile—is to replace conventional diesel fuel and gasoline with cleaner-burning fuel such as compressed natural gas, liquefied petroleum gas, ethanol, or methanol.
All of these alternatives are carbon-based fuels whose molecules are smaller and simpler than those of gasoline. These molecules burn more cleanly than gasoline, in part because they have fewer, if any, carbon-carbon bonds, and the hydrocarbons they do emit are less likely to generate ozone. The combust
A. inaccurate because it ignores consumer's concerns
B. misguided because of its exclusively technological focus
C. flawed because of the assumption on which it is based
D. invalid because it reflects the personal bias of the critics

Text 4
Although, recent years have seen substantial reductions in noxious pollutants from individual motor vehicles, the number of such vehicles has been steadily increasing. Consequently, more than 100 cities in the U. S. still have levels of carbon monoxide, particulate matter, and ozone that exceed legally established limits. There is a growing realization that the only effective way to achieve further reduction in vehicle emissions—short of a massive shift away from the private automobile—is to replace conventional diesel fuel and gasoline with cleaner-burning fuel such as compressed natural gas, liquefied petroleum gas, ethanol, or methanol.
All of these alternatives are carbon-based fuels whose molecules are smaller and simpler than those of gasoline. These molecules burn more cleanly than gasoline, in part because they have fewer, if any, carbon-carbon bonds, and the hydrocarbons they do emit are less likely to generate ozone. The combust
A. countering a flawed argument that dismisses a possible solution to a problem
B. reconciling contradictory points of view about the nature of a problem
C. identifying the strengths of possible solutions to a problem
D. discussing a problem and arguing in favor of one solution to it

Text 4 Although, recent years have seen substantial reductions in noxious pollutants from individual motor vehicles, the number of such vehicles has been steadily increasing. Consequently, more than 100 cities in the U. S. still have levels of carbon monoxide, particulate matter, and ozone that exceed legally established limits. There is a growing realization that the only effective way to achieve further reduction in vehicle emissions—short of a massive shift away from the private automobile—is to replace conventional diesel fuel and gasoline with cleaner-burning fuel such as compressed natural gas, liquefied petroleum gas, ethanol, or methanol. All of these alternatives are carbon-based fuels whose molecules are smaller and simpler than those of gasoline. These molecules burn more cleanly than gasoline, in part because they have fewer, if any, carbon-carbon bonds, and the hydrocarbons they do emit are less likely to generate ozone. The combustion of larger mo
A. be somewhat lighter in total body weight than a conventional vehicle fueled with gasoline
B. have a larger and more powerful engine than a conventional vehicle fueled with gasoline
C. average more miles per gallon than a "gasoline alone" vehicle fueled with methanol
D. have a larger and heavier fuel tank than a "gasoline alone" vehicle fueled with methanol

During recent years we have heard much about "race": how this race does certain things and that race believes certain things and so on. Yet, the (21) phenomenon of race consists of a few surface indications.
We judge race usually (22) the coloring of the skin: a white race, a brown race, a yellow race and a black race. But (23) you were to remove the skin you could not (24) anything about the race to which the individual belonged. There is (25) in physical structure, the brain or the internal organs to (26) a difference.
There are four types of blood. (27) types are found in every race, and no type is distinct to any race. Human brains are the (28) . No scientists could examine a brain and tell you the race to which the individual belonged. Brains will (29) in size, but this occurs within every race. (30) does size have anything to do with intelligence. The largest brain (31) ex
A. big
B. small
C. minor
D. major