What common type of files do document viruses typically infect?

Document viruses are specifically designed to infect files that contain text and formatting, which are commonly found in data files associated with word processing applications. These files often carry macros—small programs that automate tasks within the application. When a user opens a document file infected with a virus, the malicious code in the macros can be executed, allowing the virus to spread or perform harmful actions on the user’s system.

Data files include formats such as Microsoft Word documents (.doc, .docx), Excel spreadsheets (.xls, .xlsx), and similar types that primarily serve to hold user-generated content. These files are targeted because they are frequently shared among users, thus providing a fertile ground for virus propagation through common usage and document sharing practices.

In contrast, while pictures and audio files can be infected by other types of malware or harmful scripts, they do not typically host the kind of executable macros that document viruses take advantage of. Executable files are primarily applications or software programs that execute code directly, and while they can also be attacked or used to spread viruses, they are not the common type that document viruses infect. Hence, data files are the correct answer as they are the primary targets for document viruses.