Which type of software is specifically designed to prevent unauthorized access to a system?

Antivirus software is specifically designed to detect, prevent, and remove malicious software that can compromise a system's security. This type of software plays a crucial role in protecting computers and networks from unauthorized access, as it can identify viruses, malware, spyware, and other threats that attempt to exploit vulnerabilities. By actively monitoring and scanning for such threats, antivirus software helps to safeguard sensitive data and system integrity, ultimately preventing unauthorized users from accessing or manipulating the system.

In contrast, the other types of software listed have different primary functions. Database management software is focused on creating and managing databases, which involve structuring and organizing data rather than directly preventing unauthorized access. Spreadsheet software is used for calculations and data analysis, serving mainly business and analytical functions without inherent security measures against unauthorized access. Graphic design software is dedicated to creating and editing visual content, with no relation to system security. Thus, the role of antivirus software is unique and essential in the context of preventing unauthorized access, making it the correct choice.