Final answer:
The correct answer to the question is 'E. Till,' which refers to the unsorted debris directly deposited by melting ice sheets.
Step-by-step explanation:
The correct answer is option E. Till. Till is the term used to describe the unsorted sediment that is directly deposited by a melting ice sheet, without any sort of sorting by size or weight due to water transport. Till consists of a mixture of materials ranging from fine silt to large boulders, reflecting the diverse nature of the debris that is carried along by the ice sheet. This material accumulates as the ice melts, dropping its load of rock and sediment. It is characteristic of glacial environments and can be found laying on the surface or buried beneath newer sediments.
Unsorted debris from ice sheets is known as till. During glacial periods, ice sheets carry large amounts of sediment, including rocks, sand, and clay, which get deposited when the ice melts. This unsorted mixture of debris is referred to as till.