Which statement best describes the benefits of Cisco Integrated Services Routers？（）
- A In a single device，ISRs provide threat defense against attacks from hackers and viruses thatcan occur in the network.
- B In a single device，ISRs provide the framework to integrate and extend wired and wirelessnetworks.
- C In a single device ISRs provide concurrent security， voice， data， wireless and applicationoptimization services.
- D In a single device，ISRs provide the common fabric，functionality，and CLI across the network.