Which of the options best fits gap 15?

Directions: Fill in the gaps to make meaningful sentences.

Telephone and data networks, both private and public, provide speech or data communication -----15----two points. These two points -------16-------------at fixed locations, or if the network includes one or more switching points, any user may be able to access any other user. The network then, offered together with the associated service, is known as the value added network. Most VAN operators -----17----a combination of private lines, spare capacity on public or private networks to provide the basic network.