What defines ransomware?

Ransomware is specifically defined as a type of malware that encrypts or locks files on a victim's computer, rendering them inaccessible until a ransom is paid to the attacker. The main goal of ransomware is to extort money from the victim in exchange for a decryption key that allows access to the files again. This type of cyber threat significantly disrupts individuals and organizations, as it can result in the loss of critical data or financial resources if not effectively managed.

The other options do not accurately describe ransomware. While antivirus software is designed to prevent and remove malware, it does not demand payment for file access. Similarly, software meant to enhance computer performance does not pertain to criminal activities like ransomware. Lastly, a phishing scam involves tricking individuals into providing sensitive information, which differs fundamentally from the coercive tactics used in ransomware attacks.