Which ingredient is featured prominently in a Shirley Temple?

The key ingredient in a Shirley Temple is grenadine, which is a non-alcoholic syrup made from pomegranate juice and sugar. This syrup is responsible for the drink's distinctive sweet flavor and its characteristic reddish color. When mixed with ginger ale or lemon-lime soda, the grenadine gives the Shirley Temple its signature look and taste, making it a popular choice for a refreshing mocktail, especially for children or those avoiding alcohol.

In contrast, pineapple juice, blue curacao, and triple sec do not play a role in creating the traditional Shirley Temple. Pineapple juice is often used in tropical drinks but is not a component of this particular mocktail. Blue Curacao and triple sec are both liqueurs that are not used in a Shirley Temple, as it is meant to be a non-alcoholic beverage. Therefore, grenadine stands out as the essential ingredient in this classic drink.