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

Fact 2: Millipedes, spiders and other invertebrates are probably taken as well.

Given the two facts above, answer the question "Millipedes lack what?" with the following options: 
- epidermal
 - segmented body
 - leg pairs
 - a cuticle
 - a vertebral column
 - diplosomites
 - Chlorophyll
 - biological diversity


 

     a vertebral column    