Suppose that you have a customer who has a central HQ and six branch offices. They anticipate adding six more branches in the near future. They wish to implement a WAN technology that will allow the branches to economically connect to HQ and you have no free ports on the HQ router. Which of the following would you recommend?
Answer: C
The key is "there are no free ports" on your router. Only Frame Relay can provide a connection to multiple locations with one interface, and in an economical manner no less.