What is a macro virus?

• A. A virus written in a macro language embedded in applications like Word and Excel
• B. A virus in the BIOS
• C. A virus spread via USB drives
• D. A network worm

Answer: (A)

Macro viruses are malicious programs written in the macro language of an application, typically Visual Basic for Applications used by Word, Excel, and other Office apps. They reside inside documents or templates and run when the user enables macros, allowing the code to replicate itself into other documents and spread to others (often via email attachments or shared files). This type of malware exploits the macro capability that automates tasks, which is why the attack happens through document-based code rather than through firmware, USB autorun behavior, or network worms.

Other options point to different kinds of threats: a BIOS virus infects firmware at the hardware level; a virus spread via USB drives usually relies on removable media autorun or file infection tricks; a network worm propagates across networks by exploiting vulnerabilities or using network shares. But a macro virus specifically uses embedded macro code in documents from applications like Word or Excel.