Fact 1: An earthquake causes the ground to shake.  Fact 2: Landslides are often triggered by the shaking of earthquakes.  Given the two facts above, what causes landslides?
Pick from:
 +earthquakes.
 +deforestation.
 +scattered light.
 +rainfall.
 +Water expanding.
 +erosion.
 +mouth of rivers.
 +flooding.
earthquakes