You are presented with the question "What does an organism require for blood flow to viscera, organs, and tissues?" and the following answer choices: 
- Collagen
 - Proteins
 - energy
 - Energy.
 - food
 - blood
 - hormones
 - nutrients

Now knowing that an organism requires energy for growth and blood flows to the viscera, organs and tissues, for growth and metabolism, choose the best answer.


 

   energy      