To increase the security of the network, you have decided to implement a solution using authentication tokens. You are explaining this to a coworker who is not familiar with tokens. What are Authentication Tokens?

A.
An authentication token is a software program that is installed on each user computer. Upon execution of the program, each user will be authenticated into the network.

B.
An authentication token is a hardware device that is to be installed, either via a parallel or serial port. Once the user has installed the token, he or she will be able to access the resources on the network that they have been granted access.

C.
An authentication token is a portable device, such as a handheld computer, that stores an authenticating sequence, that the user will enter after logging into the system to gain access to network resources.

D.
An authentication token is a software program that is installed on the main server of the network. As the user is logging in, the server will instruct the user for username and password.

E.
An authentication token is a portable device used for authenticating a user, thereby allowing authorized access into a network system.