In a Fuzzy Navel cocktail, which fruit juice is used?

In a Fuzzy Navel cocktail, orange juice is the primary fruit juice used, which is central to its flavor profile. This cocktail typically combines peach schnapps with orange juice, creating a sweet and refreshing drink. The combination of these ingredients leads to a bright, citrusy taste that defines the Fuzzy Navel.

Other juices, like apple, cranberry, or grapefruit, do not contribute to the traditional flavor associated with this cocktail. Each of those juices brings its own distinct flavors that would alter the intended taste profile of the Fuzzy Navel. Therefore, the use of orange juice is crucial for maintaining the drink's signature sweetness and fruitiness, making it the correct answer in this context.