Swelling Soils Are Typically Due to ____

Swelling soils are typically due to ____.

A) kaolinite clay expelling, water which increases the volume of sand layers
B) heat, which increases the volume of water bound in clay layers
C) freezing water, which expands, increasing the volume of clay layers
D) smectite clay increasing in volume as it absorbs water
E) landslides removing pressure from clay layers, allowing them to increase in volume