You are presented with the question "what produces electricty by burning?" and the following answer choices: 
- cactuses
 - ethanol
 - engines
 - cigars
 - organisms
 - cigarettes
 - Conifers
 - ferns

Now knowing that biofuel is used to produce electricity by burning and biofuels include ethanol, methanol, biodiesel, biocrude, and methane, choose the best answer.


 

  ethanol       