Which sauce is used on the crabby patty?

The correct choice is Cajun remoulade, which is known for being a flavorful, slightly spicy sauce that complements the taste of seafood, making it an ideal pairing for a crabby patty. This sauce typically includes ingredients like mayonnaise, mustard, and various seasonings, giving it a zesty kick that enhances the natural sweetness of crab meat.

This choice emphasizes the theme of seafood and aligns with the intended flavor profile of dishes featuring crab. While other sauces like spicy mayo or garlic aioli may offer interesting flavor combinations, they do not traditionally appear as the signature sauce for crab-based dishes in popular culinary contexts. Tartar sauce, which is typically used for fish and fried seafood, lacks the distinct flavor complexity that remoulade provides in this context. Consequently, Cajun remoulade is specifically designed to enhance seafood flavors, making it the appropriate sauce for a crabby patty.