You are presented with the question "What is used to scrunch up foil?" and the following answer choices: 
- tin
 - awl
 - parchment paper
 - an external framework
 - Physical force
 - energy barrier
 - hard outer covering
 - Evaporation

Now knowing that crumple means change shape from smooth into compacted by physical force and crumple the foil then carefully reopen it, choose the best answer.


 

     Physical force    