Final answer:
Glaciers create poorly sorted sediments, known as glacial till, by transporting and depositing a wide range of sediment sizes haphazardly, unlike other agents such as waves, which sort sediments by size.
Step-by-step explanation:
The agent that creates poorly sorted sediments is glaciers. Glacial activity often picks up and transports a wide range of sediment sizes, from fine silt to large boulders, and deposits them without sorting by size. This deposit is known as glacial till. Unlike waves, which tend to sort sediments well by size due to the consistent energy of the water, or soil creep, which generally involves slow-moving soils that may sort slightly better, glaciers transport and deposit materials in a jumbled, unsorted fashion. Other agents such as wind may form well-sorted sedimentary structures like sand dunes, which showcase the power of wind to sort and transport fine sediment particles.
When considering other processes, soil creep exhibits slight sorting due to its incremental movement of soil downhill, whereas turbidite sedimentary deposits are sorted by density due to underwater slope failures. In erosional environments, the forces involved, such as river currents or ocean waves, lead to over-steepened slopes and potential landslides, but these tend to create well-sorted sedimentary layers as seen in cross-bedding and ripple marks.