You are presented with the question "What do all vertebrates have that invertebrates don't?" and the following answer choices: 
- sensory neurons
 - fur and fat
 - bones and joints
 - a jaw bone
 - kinetic energy
 - Chemical energy
 - a spinal column
 - a set of gills

Now knowing that vertebrates are all chordates that have a backbone and invertebrates are animals who lack a backbone or spinal column, choose the best answer.


 

       a spinal column  