阅读下列短文，从短文后各题所给的四个选项中，选出可以填人空白处的最佳选项。

　　Consumers and producers obviously make decisions that hold 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 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 contro1.

　　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. [中国农业银行真题]

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• A.banquet
• B.boom
• C.arena
• D.enterprise