What is the primary function of antivirus software?

The primary function of antivirus software is to detect, quarantine, and remove malware. This software is designed to recognize various types of malicious software, such as viruses, worms, spyware, and trojans, by using signature-based detection, heuristic analysis, and behavior monitoring. Once identified, the antivirus software can isolate the malware to prevent it from causing harm to the system, and ultimately remove it to ensure the system's safety and integrity.

The other options relate to different aspects of network and system management. For instance, filtering internet traffic pertains to firewall functionality, which is designed to control incoming and outgoing network traffic based on predetermined security rules. User access permissions are managed through access control systems, ensuring that only authorized users can access specific data or functionalities. Backing up system files is a critical task for data recovery and protection, but it is not within the main purpose of antivirus software. Each of these functions plays a role in overall network security, but they do not encapsulate the core responsibility of antivirus programs.