Which of the following describes a common function of antivirus software?

Antivirus software is primarily designed to detect, prevent, and eliminate malicious software, commonly referred to as malware, from computers and networks. This includes viruses, worms, trojans, spyware, adware, and other harmful programs that can compromise system security or data integrity. By continuously scanning files and monitoring system behavior, antivirus programs can identify and quarantine suspicious activities or files, offering crucial protection against cyber threats.

The other functions described in the options are essential tasks performed by different types of software. For instance, recovering lost files is typically the domain of data recovery tools rather than antivirus programs. Similarly, enhancing internet browsing speed usually falls under the functionality of browser optimization tools or software rather than antivirus software. Lastly, automatic data backup is a function attributed to backup solutions, which manage and secure data storage, rather than focusing on malware protection. Thus, the primary and defining role of antivirus software distinctly aligns with detecting and eliminating malware, making that the correct and most relevant description.