All matter can be characterized by chemical composition -- by what atoms it's made of and how they are arranged. Think of a physical change any change to the substance that doesn't alter its chemical composition (i.e. it doesn't change break or rearrange bonds, no atoms are inserted nor removed). You may see a change, but there isn't any change on the molecular level. Examples include changes in texture, color, temperature, state (i.e. from/to a solid, liquid, gas, or plasma), shape.
Now, a chemical change implies a change in the chemical composition, meaning that bonds or broken/formed between atoms. These could be indicated by a change in temperature or color, a production of scent, precipitate, or bubbles, among others. Note that a change in temperature or color does not necessarily mean that a chemical change is occurring, but increases the likelihood that it does.
To answer your question, think about what each process involves.
Fracture: breaking something into pieces
Sublime: transition of a substance from a solid to a gaseous state
Bake: adding heat to allow reactions to take place. carbon dioxide is what makes bread rise!
Ferment: yeast digests sugars in order to create alcohol
Which do you think involve changes on the molecular level versus the overall physical state?
