Why does all mammals have seven vertebrae (bones) in their neck? A) all mammals descended from a common ancestor
B) predators only eat animals with six neck vertebrae
C) all animals can turn their heads the same amount
D) all mammals have to stretch their necks to obtain food

C I hope I'm right

where is the option.let me know

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