Amphibians are the first true tetrapods, or vertebrates with four limbs, and all frogs are amphibians. Given these facts, the first tetrapods were among the following options:
- major threat to health
 - remains of prehistoric life
 - in the frog family
 - running and lifting
 - competing for resources
 - warm-blooded
 - objects that have mass
 - graptolites


 

   in the frog family      