Lactic acid fermentation occurs in?

Lactic acid fermentation occurs in the cytoplasm of the cell.

It's a form of anaerobic respiration, and occurs when oxygen is unavailable in animal (muscle) cells and in some bacteria.

i think the answer would d

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