Fact 1: Invertebrates are animals that lack a vertebral column, or backbone.

Fact 2: Fish are backboned aquatic animals.

Given the two facts above, answer the question "Fish are aquatic animals that do not lack a what?" with the following options: 
- the body's largest organ
 - furry hide
 - vertebral column
 - critical organs
 - thumbs
 - aqua lungs
 - salt and water.
 - Chlorophyll


 

   vertebral column      