Snow White Joke

Snow White and the Seven Dwarfs are roaming in the forest when they come across a lake. The water was enticing and Snow White decides to take a bath. So she tells the Dwarfs to turn around while she is taking a bath in the lake. The Dwarfs protest vehemently because they want to take a bath too.

Snow White relents and says "When I get into the water and you hear the splash, you can turn around." Snow White undresses and as she is about to jump into the water, at that very moment, she is startled by a frog who jumps into the water before she can. The moment the Dwarfs hear the SPLASH, they turn around and see Snow White standing NAKED.

Now, given that this incident is an idea for a TV ad, what product is being advertised?

That's easy ... 7 Up!