Outlook defines a(n) ____ as an activity that occurs at least once and lasts 24 hours or longer.

What type of malicious program cannot stand on its own and can replicate itself through an executable program attached to an e-mail?

A. shell B. virus C. keylogger D. rootkit

To reduce the file size of a picture, __________ it.

Fill in the blank(s) with the appropriate word(s).