What is the function of baking soda in baking?

Baking soda is primarily known for its role as a leavening agent in baking. When combined with an acid, such as vinegar or buttermilk, it reacts to produce carbon dioxide gas. This gas forms bubbles in the dough or batter, causing it to rise and become light and airy. This leavening action is crucial in many baked goods, like cakes and muffins, where a light texture is desired.

Other options, such as sweetening, preserving, or improving color, do not accurately describe the function of baking soda. Sweetening agents are typically sugars or other sweet substances, preservatives work differently by inhibiting spoilage, and color enhancement often involves ingredients like eggs or browning techniques rather than baking soda itself. This underscores the specific and important role that baking soda plays in the baking process.