What is designed to reduce or prevent unauthorized code that can corrupt data and systems?

The correct answer revolves around how virus protection functions as a critical line of defense against malicious software, which can corrupt data and systems. Virus protection is specifically designed to identify, prevent, and eliminate viruses and other types of malware from compromising the integrity of data and the functionality of systems. It employs various techniques such as scanning files, monitoring system behavior, and using heuristics to detect potential threats. By neutralizing these threats, virus protection contributes significantly to maintaining data integrity and system reliability.

Other options, while related to system security, serve different purposes. User authentication primarily focuses on validating the identity of users accessing systems and data but does not specifically address the issue of unauthorized code. Physical barriers refer to tangible security measures designed to prevent unauthorized access to facilities but are also not aimed directly at code and data integrity. Encryption protects data by encoding it, making it unreadable without the appropriate key, but it does not prevent unauthorized code execution or corruption by viruses.