You are presented with the question "what does wound healing require" and the following answer choices: 
- protein
 - nutrients
 - Enzymes
 - food
 - blood
 - amino acids
 - carbohydrates
 - cells

Now knowing that protein is used to repair cells by the human body and pain in the body indicates there is a wound which requires cell repair and cell regeneration, choose the best answer.


 

 protein        