Given the task definition and input, reply with output. In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.

These objects are often underlain by Rothlisberger or Nye channels. In one form, their movement is almost entirely controlled by Glen's Flow Law. Warm ones can also move by enhanced creep, ploughing, and regelation, and both types can experience hydraulic jacking. Many of these objects experience quasi-regular surge cycles, where their movement speed can increase a thousand-fold. These objects create a range of characteristic landforms, including kames, eskers and drumlins. For 10 points, name this class of objects found in mountainous and polar regions around the world, made entirely of ice.
Science