You can't it is automatically flagged by Litterbot.
View page
The suspicious activity was flagged by the security system for further investigation.
View page
The number of flagged questions is constantly changing. As of
July 21, 2017, there are approximately 129,991 flagged questions
and answers on WikiAnswers.
View page
Yes, you are alerted if a question on your watchlist is
flagged.
View page
On the left navigation bar. It says Flagged Questions.