Answer:
contains more fluid
Explanation:
The fluid content of the dentin tubules varies by depth, with superficial dentin containing the lowest fluid content and deeper dentin, ie, dentin closest to the pulp, containing more fluid. The amount of collagen in dentin decreases from superficial to deep dentin.
I think the answer is either three or four I am not 100% certain but I feel like the answer for this question is going to be 3
To ensure the continuity of the species
increase variation in species for natural selection to occur