Final answer:
The advocaat-based cocktail is the Fluffy Duck, a creamy drink that combines advocaat, lemonade, and sparkling water with a fruit garnish.
Step-by-step explanation:
The correct answer to the question of which cocktail is advocaat-based is A. Fluffy Duck. Advocaat is a rich and creamy liqueur made from eggs, sugar, and brandy with a smooth, custard-like flavor. The Fluffy Duck cocktail is a delightful blend that usually consists of advocaat, lemonade, and a splash of sparkling water, often garnished with a cherry or a slice of orange. It is known for its distinctive yellow color and velvety texture, which make it a festive choice for various occasions.