What type of ransomware displays a screen and prevents the user from accessing the computer's resources?

Locker Ransomware is correct answer

Explanation:

This Ransomware began to appear at the end of 2012, blocking users' computers by preventing them from logging in and displaying an official-looking message that allegedly comes from the FBI or a state police department (depending on the position of the infected computer). The message said that the user had been involved in illegal activities, such as child abuse or software piracy, and that he could avoid new actions and regain access to his computers by paying a "fine." Later versions also included software to steal passwords that remained active even if the user paid the ransom.