What are loose piles of rocks at the base of a steep slope or cliff called?

What are loose piles of rocks at the base of a steep slope or cliff called?
  a. cinder cones
  b. talus
  c. breccia
  d. debris flow
  e. regolith

What was the cause of the 2,500 deaths that occurred near Vaiont Dam, Italy, in 1963?
  a. burial by rock debris
  b. water flooding due to the breaking of the dam
  c. water flooding due to overflow of the dam
  d. burial by a mudflow
  e. the town sliding into the reservoir

What is a dip slope?
  a. It has to do with the oil dipstick in a car.
  b. The slope of a hill is parallel to the inclined layers beneath the ground surface.
  c. This describes depressions in the ground left by slumping.
  d. This refers to an abrupt increase in the steepness of the slide plane in a given landslide.
  e. This refers to slopes that are steeper than the angle of repose.

In 1985, 129 people died in a mass-wasting event in Puerto Rico. This was the highest death toll from
  such an event in U.S. history. What type of mass wasting was involved?
  a. block glide
  b. debris avalanche
  c. mudflow
  d. slump earth flow
  e. creep

What item listed below applies to block glides?
  a. rotational slide
  b. move on curved, concave upward slide surfaces
  c. the most common kind of landslide
  d. translational slide
  e. self-stabilizing

Which of the following areas is NOT known to be a region with hydrocompaction problems?
  a. Heart Mountain and Riverton areas of Wyoming
  b. Fort Collins, Colorado
  c. the Columbia Basin in Washington
  d. southwest and central Utah
  e. the San Joaquin Valley of Californi

What is the ultimate cause of mass wasting?
  a. water
  b. slope
  c. earthquakes
  d. gravity
  e. wind