A company has provided smartphones to their employees for business use. The IT administrator is required to enhance security on these devices. Which of the following would be the most effective way to upgrade security so that an employee must provide something they have in addition to something they know in order to access their device?
Installing a time-based one-time password application for access authentication.
Setting up a system which requires a PIN code after entering their password.
Disabling location services on the company-provided smartphones.
Using a fingerprint as the sole authentication method without a password.