根据以下资料回答 46～50 题 Documentary credits are separate transactions from the sales contract with which they are relat-ed and Letter of Credit can be divided into many kinds depending on the circumstance. A documen-tary credit may be available by payment, by negotiation or by acceptance. ( 46 ) means that the minated bank will pay the beneficiary the full amount due once he submits the contract documents equired under the credit. Under a ( 47 ), the beneficiary is given double assurance of payment since the confirming bank has added its own undertaking to that of the opening bank. If a credit can e transferred by the original beneficiary to one or more parties, it is a( 48 ). If a credit stipulated hat its amount can be renewed without specific amendment to the credit being made , it is then a 49 ). ( 50 )are those that cannot be amended or revoked without the consent of all the parties oncerned. 第 46 题 A．Confirmed credit B．Payment credit C．Negotiation credit D．Acceptance credit