Crevasses (Deep Fractures or Cracks)form Because ________

Multiple Choice

Crevasses (deep fractures or cracks) form because ________.

A) not all of the ice in a glacier moves downhill at the same rate in the glacier
B) as the glacier moves over irregular topography the bottom of the glacier (known as the zone of fracture) cracks and the cracks propagate upward to the surface of the glacier
C) as the glacier moves over irregular topography,the brittle upper layer or zone of fracture is subject to tension and cracks above the ductile layer
D) as the glacier moves over irregular topography,cracks can form anywhere in the glacier but they are called "crevasses" only if they are near the surface
E) there is not always the same amount of ice available in all areas so cracks form when the ice tries to move and fill in empty parts of the glacier