You are presented with the question "Cancer and tumors are a result of specific types of:" and the following answer choices: 
- organs
 - cigarettes
 - radiation
 - layers of fat
 - gene damage
 - rays or beams
 - Chemical energy
 - the skin

Now knowing that cancer is a disease in which cells divide out of control and with specific types of gene damage, the cell starts dividing out of control, forming a tumor, choose the best answer.


 

     gene damage    