Humans have
an exoskeleton
jointed appendages
segmentation
no coelom

The correct answer for the blank is-  Jointed appendages.

Appendage can be described as a part of the body that usually depicts an outgrowth in the body of an organism. Example- Legs, arms, fingers

Human beings have jointed appendages. These appendages possess bones that are linked to each other with the help of skeletal muscles, which are attached to cord like tendons that in turn are linked with bones of the appendages.

Therefore, jointed appendages is the right answer.

this is true, assuming that the allele is completely recessive and incomplete dominance is not a factor.