Which of these sauces is typically served cold?

Salsa verde is a sauce commonly served cold. It is a vibrant green sauce made primarily from fresh herbs, such as parsley or basil, blended with ingredients like garlic, olive oil, vinegar, and sometimes capers or anchovies. The fresh and bright flavors of salsa verde make it a refreshing accompaniment to various dishes, often enhancing the taste of grilled meats and vegetables when served chilled.

In contrast, beurre blanc is a warm, buttery sauce that is typically used with fish or vegetables and served immediately after preparation. Roux, which is a thickening agent made from equal parts flour and fat, is used in many hot sauces and soups, thus being inherently served warm. Alfredo sauce, made from butter, cream, and cheese, is also served hot, typically with pasta dishes. Therefore, salsa verde stands out as the only sauce in this context that is characteristically served cold.