【单选题】

Chinese currency is the Renminbi (RMB、. It is also known as "yuan". The sign of it is " ￥ ", the same as that of Japanese currency.But Japanese currency is called "yen".

The Renminbi,China’s legal tender, is issued and controlled solely by the People’sBank ofChinA、The exchange rates of the Renminbi are decided by the People’sBank ofChina and issued by the StateAdministration ofExchangeControl.China operates foreign exchange in a unified way, with the StateAdministration ofExchangeControl exercising the functions and powers of exchange control.
Before 1994, theChinese government managed the system as a dual-track foreign-exchange system. The dual-track system provided for two government-approved exchange rates, one was the official exchange rate, the other was the swap-market rate. The StateAdministration ofExchangeControl (SAEC、set the official exchange rate for the RMB、based onChina’s balance of payments and the exchange rates of her major competitor countries, such as South KoreA、In 1986, the SAEC、first set the official rates at 3.72 RMB、per dollar.
Primarily state-owned companies used the official exchange rate, mostly to buy ForeignExchangeCertificates (FECs). FECs are a separate form of currency developed in 1980 for the foreigners to use when they paid for their expenses inChinA、But, in 1994, the People’sBank ofChina stopped issuing FECs and gradually withdrew them from circulation.
The swap market, the other half of the dual-market system, was created in Shenzhen (the newly-built modern city located opposite Hong Kong) in 1985 for foreign and local businesses that had received official approval to exchange RMB、and hard currency, there were quite a lot of swap centres, the one in Shanghai being the largest.During that period, about 80 % of the hard-currency transactions in this country took place in the swap market. The swap rate was 8.7 RMB、per dollar. The dual-track foreign exchange system was not favorable toChina’s international trade and affectedChina’s application for joining the WTO. So in 1994 theChinese government decided to close the swap centres. The swap centre in Shanghai was replaced by the National ForeignExchangeCentre, which is a national inter-bank centre at which authorized banks can trade and settle foreign currencies.
"Legal tender" in the 2nd paragraph means ______.
A、currency B、Chinese currency C、legal document