51. The phenomenon associated with collision and subduction of the planet is

A. Volcanoes
B. Island arcs
C. Earthquakes
D. All of the above

52. The products of ____ are a major source of sediments for erosion and ____

A. Weathering, deposition
B. Deposition, weathering
C. Rocks, weathering
D. Rocks, deposition

53. The polar regions of the earth cannot support forest growth because

A. The growing season is short in these areas
B. The ground is often frozen or snow or ice covered
C. The rainfall is very low
D. All of these factors.

54. The part of the earth and thin layer of air above its surface, which support life on earth, are referred to as

A. Stratosphere
B. Ionosphere
C. Biosphere
D. Mesosphere

55. The ridges of the waves are where the jet stream of waves closes to the

A. Poles
B. Equator
C. Prime meridian
D. None of the above