Answer Description

The answer is VPN. A virtual private network allows a device secure access to a remote private network over an insecure medium (usually the public internet) by establishing a secure tunnel between the two. The other choices are types of networks.

Wikipedia

A virtual private network (VPN) is a mechanism for creating a secure connection between a computing device and a computer network, or between two networks, using an insecure communication medium such as the public Internet.A VPN can extend a private network (one that disallows or restricts public access), in such a way that it enables users of that network to send and receive data across public networks as if the public networks' devices were directly connected to the private network. The benefits of a VPN include security, reduced costs for dedicated communication lines, and greater flexibility for remote workers. VPNs are also used to bypass internet censorship. Encryption is common, although not an inherent part of a VPN connection.A VPN is created by establishing a virtual point-to-point connection through the use of tunneling protocols over existing networks. A VPN available from the public Internet can provide some of the benefits of a wide area network (WAN). From a user perspective, the resources available within the private network can be accessed remotely.