Mitochondria is the closest thing to the digestive system
Glycolysis evolved very early in ancestors that are common to all the domains of life.
This is because the site of glycolysis is cytoplasm which is present in both prokaryotes as well as eukaryotes.
As prokaryotes are the early ancestors of all domains of life therefore it is also considered that glycolysis is evolved very early.
The correct answer is
offspring
It would be the endocrine system
