the lowest layer of a glacier is generally
a. ice
b. dirt
c. snow
d. liquid water

Ice

Explanation:

If you dug down into the accumulation zone of a glacier, you would find three main layers. The top layer is snow that thickens further up the glacier. Below this layer is firn, a transitional layer between snow and ice, which is as hard as ice but not as dense. The deepest layer is ice.