Question: What are eskers? Group of answer choices a depression created when a fresh block of ice is left behind when a continental ice sheet melts; the ice block's melting creates the depression a U-shaped glacial trough of a tributary glacier that is topographically high above the floor of the main glacial trough that it is entering cigar-shaped hills shaped by continental ice shets deposits of sand and gravel left by a river flowing underneath a decaying continental ice sheet