Fact 1: If the amount of available food and water decreases in an environment then animals may leave that environment to find food and water.

Fact 2: Food and water provided to patients by mouth is the usual means of providing nutrition to patients.

Given the two facts above, answer the question "What do animals do when the available nutrients in an environment decrease?" with the following options: 
- basic building blocks of life
 - depress neuronal excitability
 - they leave to find them
 - they plant seeds
 - they stay
 - Plant growth is reduced
 - they live like normal
 - body temperature reduces


 

   they leave to find them      