Mr. Brown arranged for the taxi to come at six _____ she would not have to wait long at the station. [ ]

A. so that

B. even if

C. before

D. because

根据我国《支付结算办法》的规定，签发商业汇票必须记载的事项包括( )。

A．标明“商业承兑汇票”或“银行承兑汇票”字样

B．无条件支付委托和确定的金额

C．付款人名称和收款人名称

D．出票日期、出票人签章