Which term describes viruses that rewrite their entire code during each infection, making each copy unique?

Which term describes viruses that rewrite their entire code during each infection, making each copy unique?

• A. Metamorphic viruses
• B. FAT virus
• C. Shell virus
• D. Zombie

Answer: (A)

Metamorphic viruses rewrite their entire code during each infection, producing a completely new, unique copy every time. By morphing their instructions and structure, they carry out the same payload but look different at the binary level, which makes pattern- or signature-based detection far more difficult. This is distinct from other types: a FAT virus refers to where the virus infects (on FAT file systems), not how its code changes across infections; a shell virus attaches to or uses a command shell to execute, without re-creating its entire codebase each time; a zombie is a compromised host in a botnet used for tasks like DDoS, not a virus that continuously rewrites itself.

Metamorphic viruses rewrite their entire code during each infection, producing a completely new, unique copy every time. By morphing their instructions and structure, they carry out the same payload but look different at the binary level, which makes pattern- or signature-based detection far more difficult. This is distinct from other types: a FAT virus refers to where the virus infects (on FAT file systems), not how its code changes across infections; a shell virus attaches to or uses a command shell to execute, without re-creating its entire codebase each time; a zombie is a compromised host in a botnet used for tasks like DDoS, not a virus that continuously rewrites itself.