Final answer:
Continental ice sheets are the most abundant type of glaciers on Earth by volume, encompassing significant ice volumes in Antarctica and Greenland. The correct answer is option c.
Step-by-step explanation:
The most abundant types of glaciers on Earth today, in terms of total volume, are continental ice sheets. These are massive expanses of ice that cover large areas of land, including the continents of Antarctica and Greenland. The Table 9.6 in our reference indicates that about 90% of the ice volume is in the Antarctic ice sheet, with another 10% in the Greenland ice sheet. These ice sheets far exceed the volume found in smaller glacier types such as valley glaciers, alpine glaciers, and cirque glaciers.