Which of the following statements regarding Huawei AR series routers are true? (Multiple Choice)

Which of the following statements regarding Huawei AR series routers are true? (Multiple Choice)
A . Huawei AR series routers provide the security, routing, switching, VPN, and wireless functions to ensure secure, fast, and reliable data forwarding
B . Huawei AR series routers provide security control mechanisms, including control on intranet access and user permission, to ensure the security of access to enterprise intranets and isolate the departments of an enterprise.
C . Huawei AR series routers guarantee user-specific QoS and service-specific QoS and flexibly allocate bandwidth for various services.
D . Huawei AR series routers provide the attack defense function to protect user traffic against attacks from the extranets and intranets.

Answer: ABD