You are presented with the question "Glass or fiberglass buildings are used to protect plants by keeping them what?" and the following answer choices: 
- mild
 - heat
 - hibernating
 - cooled
 - warm
 - warmth
 - cold
 - frozen

Now knowing that agreenhouse is used to protect plants by keeping them warm and hobby greenhouses used to be small glass houses or fiberglass buildings, choose the best answer.


 

     warm    