Fact 1: Vertebrates are animals that have a backbone.

Fact 2: Jaws appear within the vertebrates.

Given the two facts above, answer the question "what appear within animals that have a backbone?" with the following options: 
- animals without backbones
 - nerves
 - californium
 - otters
 - muscle
 - jaws
 - Birds
 - fingernails


 

      jaws   