CompTIA Security+ Question H-95

Internet banking customers currently use an account number and password to access their online accounts. The bank wants to improve security on high value transfers by implementing a system which call users back on a mobile phone to authenticate the transaction with voice verification. Which of the following authentication factors are being used by the bank?

A. Something you know, something you do, and something you have
B. Something you do, somewhere you are, and something you have
C. Something you are, something you do and something you know
D. Something you have, something you are, and something you know

Answer: C