Myra puts kernels of wheat in a grinder and grinds them into flour. She then adds salt,
baking soda, sugar, and dry yeast and mixes them together. (Yeast is a live organism
that lives off of simple sugars and gives off carbon dioxide gas as it eats the sugars.)
Next, she adds water, milk, and oil. She kneads the mixture to form dough. She lets the
dough rise until it doubles in size. Then, she punches it down, forms a loaf, and places it
in a bread pan. She lets it rise again, and then she bakes it in the oven.

Which of the following steps involves a chemical change?

A)She lets the dough rise until it doubles in size.

B)She adds salt, baking soda, sugar, and dry yeast to the flour and mixes them together.

C)Myra puts kernels of wheat in a grinder and grinds them into flour.