Continue writing the next sentence in this paragraph:

How to distinguish between a' rogue antivirus' and a' legit' one
Memorize a few names of " legit " antiviruses.
This way you may know which is rogue and which is legit. A few legit antiviruses are mcafee, avg, avast! , norton, and kaspersky.
Some of these are free (like avast and avg) and some of these have a trial version and a paid version (like norton or mcafee). Memorize a few names of rogue antiviruses as well.