资金结算网络的服务渠道不包含以下哪一种（）。
A、对公营业机构
B、重要客户服务系统
C、网上银行企业客户服务系统
D、手机银行与短信银行系统
参考答案：D
Our club is open to adults only. ______ your children have entered without permission. [ ]
A. There seems that
B. It seems to be
C. There seems to be
D. It seems that
气密性实验时一次除尘器紧急放散阀应在（）位置。
A.关
B.开
C.微开
