You are presented with the question "What can affect genes that control the cell cycle?" and the following answer choices: 
- Leptospirosis
 - acetic acid
 - water vapor
 - Smoking
 - butter
 - radiation
 - resistance
 - gasoline

Now knowing that mutations that lead to cancer usually occur in genes that control the cell cycle and radiation causes mutation, choose the best answer.


 

      radiation   