c. Two-factor authentication
Explanation:
The type of security measure that is being described is known as Two-Factor authentication. This is a security measure in which an individual is only granted access after successfully presenting two or more pieces of evidence to an authentication mechanism. These two forms of evidence can vary from service to service, for example a company may require that the user enter a password and a fingerprint scan, or may ask for a password and SMS code sent to the individual's phone.