The correct answer is lactic acid fermentation.
Lactic acid fermentation refers to a metabolic procedure by which glucose and other six-carbon sugars, like lactose or sucrose are transformed into cellular energy and the metabolite lactic acid that is a lactate in solution.
It is an anaerobic fermentation reaction, which takes place in certain kinds of bacteria and animal cells, like muscle cells.
C. The cell took in another ancient prokaryotic cell, which began living inside it.
