A security technician wants to implement a two-factor authentication method for his network. The users on
his network already have passwords.
Which of the following could the technician use in conjunction with passwords to accomplish this goal?
(Select the best answer.)
O A. a personal identification number (PIN) that the user chooses and can change at any time
O B. the answer to a security question
O C. a numeric code automatically generated by a smart phone application
O D. a personal identification number (PIN) that is assigned to the user and never changes