[单选题]25. A user is complaining of being unable to open external or internal URLs directly or from the bookmark list. What could be the problem?一个用户正在抱怨不能直接打开内部的或者外部的URL或者不能从书签打开它们，什么原因导致这个问题?
A.The use is not really connected to the SSL VPN. 用户并没有真正连接到SSL VPN
B.The user is connected to somebody else's SSL VPN. 用户连接到其他人的SSL VPN了
C.The user has not been given an IP address by the ASA．用户还没有得到ASA分配的IP地址
D.The administrator has not configured a DNS server group. 管理员还没有配置一个DNS 服务器组
E.The ASA device has experienced a blue screen error. ASA设备已经经历了—个蓝屏错误
F.The administrator has not configured a hostname. 管理员还没有配置主机名