It’s C because at higher temperatures particles move faster
They have two pairs of main nerve cords organized around a number of paired ganglia. while they don't have a "true brain"-- they have somewhat of a nervous system, composed of the two, or three pairs of nerve cords contained in the visceral mass.
The answer is <span>A. The two animal species are very closely related.
If the two animal species are very closely related, that means their genome information is very similar and that information for embryonic development is also very similar, but it will not be identical. Stages of embryonic development from the beginning to the end are same only in the same species. In different species, they will differ in lesser or greater extent which depend on how closely this different species are related.</span>
Gyri form the top of the ridges, while sulci form the " valley" of the ridges.