What key ingredients are used in a Moscow Mule?

The Moscow Mule is a classic cocktail that specifically features ginger beer as one of its main ingredients, providing a unique spiciness and carbonation that sets it apart. The other key component is citrus flavors, typically from freshly squeezed lime juice, which adds brightness and acidity to balance the sweetness of the ginger beer. This combination creates the distinct taste profile that defines a Moscow Mule.

While the other options present different types of beverages, they do not encompass the fundamental ingredients of a Moscow Mule. For instance, rum and mint are characteristic of a Mojito, while vodka and lemonade might refer to a different vodka-based cocktail. Whiskey and ginger ale also do not align with the traditional ingredients of a Moscow Mule, which solely features vodka alongside ginger beer and lime. By highlighting both ginger beer and citrus flavors, the correct answer captures the essence of the Moscow Mule.