During a high-energy athletic event, such as a sprint, most of the energy that is provided to the muscles comes from glycolysis. the electron transport chain. the krebs cycle. fermentation.

The most appropriate answer should be fermentation.

Sprint refers to the high-intensity exercise in which an athlete runs at his or her full speed for a short period of time.  

Due to high intensity, the oxygen level decreases in the muscles and they undergo lactic acid fermentation.

It results in the depletion of glycogen reserve in the muscles as glucose is being used in the fermentation in order to provide energy.

Due to the build of lactic acid in the muscle, the athlete would feel burning effect and cramps in the muscles.  

It decreases the performance of the athlete after sometimes.

"a.) well–developed vascular system."

this is a good question! i'll do some research and come back when i have the answer!