A virus scanner is running on a computer and scans all files currently in use. Why should a full scan be performed periodically?

A. Files not accessed recently may contain a virus.
B. A full scan optimizes all files on the hard drive.
C. A full scan resets the archive bit on the file.
D. Active antivirus software only scans the C:\WINDOWS directory.

Answer: A. Files not accessed recently may contain a virus.