This cockroach is an insect, and the dog is a mammal. Insects and mammals both have structures that support their bodies. What is a major difference between these structures?
F. Insects support their bodies poorly, and mammals do it well.
G. Insects’ support structures are in their heads, and mammals’ are in their bodies. H. Insects have mainly external support, and mammals have mainly internal support.
I. Insects leave behind their support structures when they move, and mammals keep theirs