Choose the words or expressions to complete the passage(选择最恰当的单词或词语，完成短文)
For many years the United States and the other countries used gold and silver as money. Paper money was used to stand for the holdings(储备)of both gold and silver. The value of silver was limited to that of gold. Fifteen ounces(盎司) of silver had the same value of one ounce of gold. These values did not change until after 1860 when mines(银矿)in the west of the United States began to  1  large amounts of silver. This extra amount of silver caused the price of silver to 2     . Then fifteen ounces of silver would no longer buy one ounce of gold. In 1871 Germany declared(宣布)that it would not support its paper money with silver any more. Instead, it would use only gold. Other countries of Europe quickly  3  the same. The United States passed a law in 1973 that prevented the government from using silver as money. Western silver producers protested(抗议)loudly and put much pressure on the  4  makers. Five years later a new law was 5  . It said that the government must buy four and half million ounces of silver each month. The new law increased the amount of silver money. The country had two kinds of quite different views on the issue(发行)silver money. Businessmen, bankers and other rich men wanted to 6   the use of silver money because it made the dollar less valuable. But farmers, laborers and the others who owned the money not only wanted silver money but also wanted an unlimited supply of it.

A．produce B．find C．search D．dig

A．rise B．lift C．fall D．set

A．did B．took C．made D．acted.

A．law B．money C．gold D．silver

A．refused B．accepted C．planned D．passed

A．end B． continue C．protect D．allow