Which virus type blocks access to target machines or provides victims with limited access to the system?

Which virus type blocks access to target machines or provides victims with limited access to the system?

• A. System Sector Virus
• B. Macro virus
• C. Encryption viruses
• D. Stealth virus

Answer: (C)

Ransomware-style behavior is all about denying access to data or limiting how the system can be used. An encryption virus does exactly that by encrypting the victim’s files so they’re unreadable, effectively blocking access. The attacker may then demand payment for a decryption key. That direct effect—rendering data inaccessible through encryption—is what the scenario describes. Other malware types don’t center on locking data: a system sector virus targets the boot sector to affect startup and persistence, a macro virus spreads through documents via macros, and a stealth virus hides its presence while remaining active. None of these primarily aim to encrypt files to block access, so encryption viruses fit the described behavior best.

Ransomware-style behavior is all about denying access to data or limiting how the system can be used. An encryption virus does exactly that by encrypting the victim’s files so they’re unreadable, effectively blocking access. The attacker may then demand payment for a decryption key. That direct effect—rendering data inaccessible through encryption—is what the scenario describes.

Other malware types don’t center on locking data: a system sector virus targets the boot sector to affect startup and persistence, a macro virus spreads through documents via macros, and a stealth virus hides its presence while remaining active. None of these primarily aim to encrypt files to block access, so encryption viruses fit the described behavior best.