______his arrival at the classroom on his first day at school, the teacher _______. [ ]

A. At; was played a trick on                  

B. On; played a trick at his students

C. To; played a trick on his students            

D. On; was played a trick on

个人网银客户凭用户名和登录密码使用网银渠道服务，涉及资金支出类交易需验证以下哪一项内容（）

A.开户日期

B.登录密码

C.用户名

D.凭证密码