This type of virus infects programs that can execute and load into memory to perform predefined steps for infecting systems. It infects files with the extensions .EXE, .COM, .BIN, and .SYS. As it…

A polymorphic virus mutates its own code with each infection to evade signature-based detection - its defining trait is code mutation, not targeting executable file extensions.

A stealth virus hides its presence by intercepting OS calls to mask changes to files or the boot sector, which is a concealment mechanism rather than a description of what file types it targets.

A boot sector virus infects the master boot record or volume boot record of a disk, not program files with .EXE or .COM extensions.

A file virus specifically targets executable files with extensions such as .EXE, .COM, .BIN, and .SYS, infecting them when they are loaded into memory and executed, which can corrupt or destroy the operating system files and require reinstallation.

A multipartite virus infects both the boot sector and executable files simultaneously, making it a hybrid type rather than a purely file-targeting virus.