What type of services are provided by the Cisco IOS gateways in a VoIP network with Cisco CallManger functionality？（）

• A、Cisco IOS gateways provide services such as address translation and network access control for the devices on the network
• B、Cisco IOS gateways provide services such as bandwidth management and accounting
• C、Cisco IOS gateways provide media termination and signal translation between the public switched telephone network （PSTN） and IP networks
• D、Cisco IOS gateways provide zone management for all registered endpoints in the network