Consumers and producers obviously make decisions that mold the economy, but there is a third major     1    to consider the role of government. Government has a powerful     2    on the economy in at least four ways:
    Direct Services. The postal system, for example, is a federal system     3    the entire nation, as is the large and complex establishment. Conversely, the construction and     4    of most highways the     5    of the individual states, and the public educational systems, despite a large funding role by the federal government, are primarily     6    for by country or city governments. Police and fire protection and sanitation     7    are also the responsibilities of local government.
    Regulation and Control. The government regulates and controls. Private     8    in many ways, for the     9    of assuring that business serves the best     10    of the people as a whole. Regulation is necessary in areas where private enterprise is granted a     11    , such as in telephone or electric service. Public policy permits such companies to make a reasonable     12    , but limits their ability to raise prices     13    , since the public depends on their services. Often control is     14    to protect the public, as for example, when the Food and Drug administration bans harmful drugs, or requires standards of     15    in food. In other industries, government sets guidelines to ensure fair competition without using direct control.
    Stabilization and Growth. Branches of government, including Congress and such entities as the Federal Reserve Board attempt to control the extremes of boom and bust, of inflation and depression, by     16    tax rates, the money supply, and the use of credit. They can also     17    the economy through changes in the amount of public spending by the government itself.
    Direct Assistance. The government provides many kinds of help to     18    and individuals. For example, tariffs     19    certain products to remain relatively free of foreign competition; imports are sometimes taxed so that American products are able to     20    better with certain foreign goods. In quite a different area, government supports individuals who cannot adequately care for themselves, by making grants to working parents with dependent children, by providing medical care for the aged and the indigent, and through social welfare system. 
 
【正确答案】 D
【答案解析】 名词词义辨析。此处是把the role of government和consumers and producers相提并论,共同作为影响经济的“元素”。故答案为D。