People have been left scratching their heads over a brainteaser designed to weed out ‘geniuses’ from the average folk.

If you can solve it correctly, and within a short timeframe, you likely have a high IQ and could be a great person to have around when a crisis strikes.

Taking to Reddit to share the brainteaser, a user said: “Four people (A,B,C,D) want to cross a bridge. It’s too dark, so they have to cross a bridge with a flashlight.

“The bridge is too old, so only two people can cross it at…