Computers on the network are frequently infected with viruses, malware, worms and Trojans. Which of the following should Mike, a technician, update automatically to prevent future problems?

Antivirus signatures are definition files that contain the fingerprints of known viruses, malware, worms, and Trojans. New malware is released constantly, so automatic daily (or more frequent) signature updates are essential to ensure the antivirus engine can recognize and block the latest threats before they execute. Without current signatures, the engine cannot identify newly discovered malicious code even if its scanning engine is fully up to date.

The antivirus engine (the scanning software itself) is updated far less frequently through software version releases, not the daily automatic updates that protect against new threats.

'Malware engines' is not a standard industry component updated automatically; malware detection relies on the antivirus engine combined with signatures.

'Virus encyclopedias' are informational reference databases, not the active definition files used by antivirus software to detect threats in real time.