Which is an example of a physical change? A) Mixing blue and yellow paint to create green paint

B) Adding water and yeast to bread dough in order to make it raise.

C) Mixing two liquids together in a test tube and the tube becoming warm.

D) Adding a piece of chalk containing calcium carbonate to a glass of mild acid causing the information of a foam of bubbles.

A physical change is a change in appearance only. The matter is still the same after the change takes place. Examples of physical change include, cutting paper, melting butter, dissolving salt in water, and breaking glass. A chemical change occurs when matter is changed into one or more different types of matter.

Explanation:

hope this gives you a idea of which one is the answer

that's what i got you can count the number of atoms