Explanation: IEEE 802.1X is standard which stands for Port-based Network access control (PNAC). The authentication process of IEEE 802.1X is accessing should be managed through server, presence security factor , policies of network are managed and supported by network policy server .
The device that want to be connected with LAN or wireless LAN get though this authentication process.Other options are incorrect because files services, web servers and active directory domain services are not the factor that considered for authentication in IEEE 802.1X.
A computer keyboard is an input device that allows a person to enter letters, numbers, and other symbols (these are called characters in a keyboard) into a computer. Using a keyboard to enter lots of data is called typing. A keyboard contains many mechanical switches or push-buttons called "keys".
