Which common ingredient is used to thicken sauces and soups?

Flour is commonly used to thicken sauces and soups due to its ability to absorb liquid and create a creamy texture. When flour is mixed with a fat, usually in a roux, and then combined with liquid, it helps create a smooth consistency while also enhancing the flavor of the dish. This thickening method is widely utilized in various recipes, from gravies to cream sauces, making flour a staple ingredient in culinary techniques aimed at achieving a thicker consistency.

Other options like rice may be used in some soups for texture but do not serve primarily as thickening agents. Rye can also add flavor but does not function well as a thickener compared to flour. Sugar, on the other hand, is used mainly for sweetness and does not contribute to the thickening of sauces or soups. Thus, flour stands out as the most effective and traditional option for this purpose.