Which interface-level command is needed to turn on 802 1X authentication?

Which device acts as an authenticator during the 802.1X authentication process?

Which nodes are supported in a distributed Cisco ISE deployment? (Choose two.)

An administrator is configuring TACACS+ on a Cisco switch but cannot authenticate users with Cisco ISE. The configuration contains the correct key of Cisc039712287. but the switch is not receiving a response from the Cisco ISE instance What must be done to validate the AAA configuration and identify the problem with the TACACS+ servers?

An engineer is working with a distributed deployment of Cisco ISE and needs to configure various network probes to collect a set of attributes from the endpoints on the network.
Which node should be used to accomplish this task?