Brain Teaser - The Three Light Bulbs

You are in a room with three switches labeled A, B, and C. Each switch controls one of three light bulbs in another room, which you can't see. Initially, all the light bulbs are turned off. You are allowed to toggle the switches however you like, but once you enter the room with the light bulbs, you cannot change the switches again. How can you determine which switch controls each light bulb with only one visit to the room with the bulbs?

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