The correct answer is option 4: "It does not contain sodium bicarbonate." This statement is correct. Baking powder actually contains sodium bicarbonate as one of its main ingredients. Sodium bicarbonate is a leavening agent that helps to create carbon dioxide gas, which causes the dough or batter to rise.

Let`s analyze the other options to understand why they are not the correct answer:

1. Option 1: "It is a mixture." This statement is correct. Baking powder is indeed a mixture of multiple ingredients, including sodium bicarbonate, an acid (such as cream of tartar), and a moisture-absorbing agent (such as cornstarch).

2. Option 2: "It forms bubbles in a wet mixture." This statement is correct. The reaction between the acid and the sodium bicarbonate in baking powder produces carbon dioxide gas, which forms bubbles in the wet mixture, causing it to rise.

3. Option 3: "It can be used instead of using yeast." This statement is correct. Baking powder is a leavening agent that can be used as a substitute for yeast in recipes. It works by releasing carbon dioxide gas when exposed to moisture and heat, resulting in the rise of the dough or batter.

In conclusion,