【单选题】Each of the following statements about central banks of countries and foreign exchange markets is true except:
A.
The central banks are generally major players in the foreign exchange market.
B.
Most central banks actively manage their foreign exchange reserves with the purpose of generating trading profits from favorable exchange rate movements.
C.
A modeling of central bank intervention in the foreign exchange market sometimes helps to understand short-term behavior of exchange rates.
D.
Central banks may intervene in the foreign exchange market for the implementation of the monetary policy and exchange rate targets.
【单选题】When two banks agree to be correspondents with each other, they first exchange their______to verify signatures with authorized ones for different transactions.