The correct answer is option 1: Transmission Control Protocol/Internet Protocol (TCP/IP).

TCP/IP is a set of protocols that governs the communication of data over the internet. It was first developed in the early 1970s by Vinton Cerf and Bob Kahn, and it has been continuously evolving and improving over the years. By January 1st, 2013, TCP/IP had completed thirty years of development.

Option 2: Computer Network is not the correct answer because while TCP/IP is an essential component of computer networks, it is not the same as a computer network itself. A computer network refers to the interconnected system of computers and other devices that communicate and share resources.

Option 3: Social Networking Sites is not the correct answer because TCP/IP is not specific to social networking sites. Instead, it is a fundamental technology that enables communication between all types of devices and applications on the internet.

Option 4: Network Control Protocol (NCP) is not the correct answer because NCP was the initial protocol used in the ARPANET, which predates TCP/IP. TCP/IP replaced NCP and became the standard protocol for internet communication.