Sharpening an object causes that object to change shape, and very often their only metal object in the house is a cooking pot or a knife. Given these facts, what does sharpening a knife do among the following options:
- change its material
 - make it stay the same
 - lowered energy cost
 - duplicate itself
 - Relieve pain
 - change its shape
 - change its color
 - It gets heated up


 

      change its shape   