Final answer:
Groundwater contains the next highest percentage of the Earth's freshwater after ice sheets and glaciers, with approximately 30.1% of the Earth's fresh water.
Step-by-step explanation:
After ice sheets and glaciers, which are the largest reservoirs of the Earth's freshwater, the next highest percentage of the Earth's freshwater is found in groundwater. Glaciers and ice caps hold a significant 68.7% of freshwater, whereas groundwater accounts for approximately 30.1% of Earth's freshwater. In comparison, lakes and rivers hold much smaller quantities with lakes at 0.86% and rivers at 0.02% of Earth's freshwater. Among these options, groundwater represents the largest accessible source of fresh water for human use.