If adequate o2 is present in the mitochondria, pyruvic acid will be converted to ; if conditions are anaerobic, pyruvic acid will be converted to

Presence of Oxygen in mitochondria is called Aerobic conditions and under this aerobic conditions Pyruvic acid is converted into Acetyl Co.A which enters Krebs' cycle
while in absence of oxygen which called Anaerobic conditions pyruvic acid is converted into Lactic acid to avoid accumulation of NADH⁺ which inhibit glycolysis and provide NAD⁺ required for glycolysis  

It’s the energy source of stars

While unproven, it uses facts to support part of a conclusion. it is still factual and has predictive power, however.