You are presented with the question "What are vertebrates with four limbs?" and the following answer choices: 
- humans
 - frogs
 - fish
 - Birds
 - phytoplankton
 - coral
 - bears
 - goats

Now knowing that amphibians are the first true tetrapods, or vertebrates with four limbs and all frogs are amphibians, choose the best answer.


 

  frogs       