Fact 1: Apesticide is used for protecting plants by killing insects.

Fact 2: Pesticide use requires disposal of either excess pesticides or empty pesticide containers.

Given the two facts above, answer the question "What does something used for protecting plants by killing insects require?" with the following options: 
- electricity
 - hydrogen and oxygen
 - organic molecules
 - food and shelter
 - important habitats
 - Special disposal
 - chemical messengers
 - deoxyribonucleic acid


 

      Special disposal   