You are presented with the question "What ccurs when many muscles contract a little bit all at once?" and the following answer choices: 
- heat production
 - heat loss
 - sweating
 - permineralization
 - hypothermia
 - resistance
 - cramping
 - heat energy

Now knowing that shivering occurs when many muscles contract a little bit all at once and heat production is increased by shivering and non-shivering thermogenesis , choose the best answer.


 

 heat production        