Approximately 1.5 minutes of intense exercise will obtain atp mostly from which process (think sprinting) :

The correct answer is anaerobic (fast) glycolysis.

This is a special type of glycolysis when limited amounts of oxygen (O2) are available, so the glucose is transformed to lactate (lactic acid). Because the end product of anaerobic glycolysis is lactic acid, it can accumulate and potentially lead to muscular fatigue.