Which is a metabolic product of glycolysis during exercise?

Correct option is D

During exercise, glycolysis is the process where glucose is broken down into pyruvate to generate energy in the form of ATP. Under normal aerobic conditions (with enough oxygen), pyruvate enters the mitochondria to undergo further processes like the citric acid cycle. However, during high-intensity exercise when oxygen supply is limited (anaerobic conditions), pyruvate is converted into lactate (also known as lactic acid) to continue glycolysis and produce ATP quickly.