What happens during the Krebs cycle

Explanation:

the Krebs cycle occurs on the mitochondrial matrix and generates a pool of chemical energy from the oxidation of pyruvate, the end product of glycolysis. pyruvate is transported into the mitochondria and loses carbon dioxide to form acetyl-CoA, a 2-carbon molecule

the correct answer is c   with the systems

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