Fact 1: Agreenhouse is used to protect plants from the cold.

Fact 2: Greenhouse plants grow healthier.

Given the two facts above, answer the question "plants grow healthier if they are protected from what" with the following options: 
- cold
 - soil
 - forces
 - mold
 - sun
 - loss
 - mildew
 - rain


 

 cold        