London: Facebook users have to change their profile pictures to a giraffe if they fail to solve a riddle shared on the social networking site.
The riddle, which has nothing to do with the African mammal, is said to be easy to solve, but is tripping many users up as it spreads around the site.
According to the Metro, the question asked in the challenge is: `It`s 3am, the doorbell rings and you wake up. Unexpected visitors! It`s your parents and they are here for breakfast. You have strawberry jam , honey, wine, bread and cheese. What is the first thing you open?`
(Answer given in the end of the article)
Facebook users who have failed the challenge must change their profile pictures on the site to a photo of a giraffe and re-post the riddle, asking friends to message them with the answer.
If the friends also answer the riddle wrong, they must change their profile picture and post the riddle for their friends to guess, thus spreading the game further on Facebook.
The answer is:
`You open the door first` and `you open your eyes first` have both been accepted as answers by those posing the riddles on Facebook.