You've come to our website, which offers answers for the Brain Test 4 game. This webpage with Brain Test 4 Worry must turn on all of the light bulbs answers is the only source you need to quickly skip the challenging level. This game is made by developer Unico Studio, who except Brain Test 4 has also other wonderful and puzzling games.
You can never turn them all on with the 4th one. Tap on the 4th one's cable to break it.