Answer:
Blocking ransomware
Step-by-step explanation:
A ransomware is a malware that acts by encrypting the files of a victim after which the attacker demands for a ransom payment to be made by the victim before access is restored through the provision of a key to decrypt the encrypted files
There are different types of ransomware such as blockers, wipers and cryptors
A blocker ransomware is one that blocks access to the files stored on a computer or device by encrypting them and usually displaying a demand for payment message that comes up in front of the all opened windows