Here's a problem to solve: Missy and Ethan discussed examples of the types of changes in matter. In which example is a chemical change taking place?

Among the 4 following options, which is the correct answer?

- A: A piece of metal is cut in half.
 
- B: An ice cube melts on a counter.
 
- C: A camper roasts marshmallows over a burning fire.
 
- D: A baker mixes together flour and sugar to make dough.
 