Crumple means change shape from smooth into compacted by physical force, and crumple zones and bumpers are often weaker and poorer performing than in cars. Given these facts, what part of a car easily changes shape from smooth to compacted by physical force among the following options:
- rock
 - arteries
 - fender-bender
 - an object
 - bumper
 - wreck
 - Gravity
 - sedan


 

     bumper    