Option C - vinegar bubble when baking soda is added is a chemical change and it is correct.
Chemical change is a chemical reaction that occur when a substance combine with another to form a new substance. Chemical reactions are not reversible except by further chemical reactions. The options above, only option C is a Chemical change.
A lake freezes to ice is a physical change and can be turned back to water. A metal bar is rolled into a flat sheet can be reversed back to its normal state. Sand, water and salt combined to form a mixture is also a physical change.