What term describes the debris ridges left by glaciers?

The term for debris ridges left by glaciers is a moraine.

A moraine is an accumulation of rock fragments, sediment, and other unconsolidated debris transported or deposited by a glacier. Moving ice acts like a conveyor belt and bulldozer: it carries material from valley walls and the glacier bed, then leaves that material behind as the ice advances, pauses, or melts.

Moraines are named by their position and formation. Lateral moraines run along a glacier’s sides, while medial moraines form down the center when two glaciers merge. Terminal moraines mark a glacier’s farthest advance, and recessional moraines form as the glacier pauses during retreat. Ground moraines are broad blankets of till deposited beneath or behind the ice.

The alternatives describe different glacial landforms. Drumlins are streamlined hills shaped beneath moving ice, eskers are winding ridges of sediment deposited by meltwater streams beneath or within glaciers, and kettles are depressions left when buried blocks of ice melt. A moraine is specifically the debris accumulation or ridge associated with glacial transport and deposition.