有如下tnsnames.ora 文件: test = (description = (address_list = (address = (protocol = tcp)(host = serv2)(port = 1521)) ) (connect_data = (service_name = prod) ) ) prod = (description = (address_list = (address = (protocol = tcp)(host = serv1)(port = 1521)) ) (connect_data = (service_name = prod) ) ) dev = (description = (address_list = (address = (protocol = tcp)(host = serv2)(port = 1521)) ) (connect_data = (service_name = dev) ) ) 对于连接串test, prod和dev，下面哪些说法是正确的？CD A test连接串会失败，因为连接串和服务名不匹配 B serv2存在端口冲突，因为prod和dev服务使用相同的端口 C 三个都是有效的 D 如果实例设置使用动态注册，所有三个都能成功