Which of the following are the primary leavening agents used in barley preparation?

Explanation

The main leavening agents employed in barley products are yeast and sodium bicarbonate. Yeast acts as a biological leavening agent by fermenting sugars to produce carbon dioxide, while sodium bicarbonate serves as a chemical leavening agent releasing gas upon heating. Sugar is not primarily used as a leavening agent but may serve other roles such as flavor enhancement.