New Delhi, Oct. 21 -- Optical illusions are a great way to challenge the brain. Since they present themselves in the forms of numbers, puzzles, and mind-boggling images, users are forced to exercise their minds and think out of the box. A new Reddit image, which has gone viral, has people putting their brains to the test and identify a 'dangerous' cow in a group of cattle. Since most of the animals look alike, the challenge for the users is to report the odd one out "immediately."

The image shared by r/FindTheSniper on Reddit has got the users scratching their heads. The user has challenged the audience to spot the 'dangerous' cow out of the many look-alikes. While the challenge is to solve the puzzle within or less than 10 seconds, many...