Here Is Your Tuesday Morning Trivia Question!

If I didn't know any better, I would think that summer is already over.  It is supposed to be spring and there is snow on the ground and the temperature is in single digits.  So, to take your mind off of this crappy weather I have a good trivia question for you today.

Today's trivia question has to do with world flags.  Don't worry though, it's not as hard as you might think.  Here is Today's Trivia Question:

What color appears in more flags around the world than any other?