Fact 1: Endocrine hormones travel throughout the body in the blood.

Fact 2: Puberty leads to hormonal and sexual changes.

Given the two facts above, answer the question "Puberty leads to sexual changes that travel throughout the body in what?" with the following options: 
- blood
 - A drug.
 - hair
 - sleep
 - painful
 - years
 - eyes
 - chest


 

 blood        