A student squeezes a clothespin as rapidly as possible for one minute. Without stopping to rest, the student continues to squeeze the clothespin for a second minute. At the end of the second minute, the student's fingers and hand feel very cramped and tired. The physical tiredness and cramping in the muscles in the student's hand were most likely due to the increased production of
1. ATP
2. waste of products
3. oxygen
4. glucose