Name a carbonated mixer you might use in a cocktail.

Club soda is a popular carbonated mixer used in cocktails, known for its effervescence and ability to add a pleasant fizz without overpowering the flavor of other ingredients. It is often utilized to lengthen drinks, providing volume and texture while maintaining a light taste. This makes it a versatile choice in many classic cocktails, such as Tom Collins or a simple highball.

In contrast, while orange juice, sugar syrup, and cranberry juice are all common cocktail ingredients, they are not carbonated. Orange juice is a fruit juice that adds sweetness and acidity, sugar syrup is used to enhance sweetness without altering the drink's texture, and cranberry juice provides a tart flavor and vibrant color, but none of these options introduce carbonation to a cocktail. Thus, club soda stands out as the correct choice for a carbonated mixer.