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The answer is D. Kidneys absorb more water,volume of water lost from the skin increases and the hairs on the skin lie flat

the cladogram shown here shows similarities and differences among several classes of vertebrates. anatomically, the four have limb structure as their common ancestor. we might separate the mammals from the other three classes because they a) divergent; do not lay eggs b) identical; are warm-blooded c) varied; a four chambered heart d) homologous; have mammary glands

c is the correct answer hope this !