You are presented with the question "What stimulates the reproductive organs to develop into male organs?" and the following answer choices: 
- a hormone
 - bioaerosols
 - Energy.
 - Energy
 - Leptospirosis
 - a doorbell
 - seeds
 - Chlorophyll

Now knowing that testosterone stimulates the reproductive organs to develop into male organs and for men, however, the hormone in question is testosterone, choose the best answer.


 

 a hormone        