I try to do a kind of Advent calender here. More or less every day I post an image (animation, live-action, newspaper) with one area completely desaturated. Underneath the picture you'll see different color swatches one of which matches the now desaturated area in the original picture. If you think you know the correct color, write a comment with the letter corresponding to the color swatch. Of course you could always guess, it’s multiple choice after all. I will withhold comments for at least the day after, so that you don’t see what other people already have guessed. As long as you don't see any comments on a post you can still answer, even if the next one is already up.
Then I will also post the original image. There might also be additional questions like trivia.
I hope I still have time for regular posts, though.
If I get three answers I will continue, else I will stop posting those images.
I'm putting together a list of participants just for fun to see who got the most answers right.