Answer:
D. All of the above.
Step-by-step explanation:
Soil compaction is termed as the compression of particles of small to small volume which are then reduces their pore space size which is being available for water and air.
Soil compaction can result from;
1. Elimination or reduction of pore space in soil.
2. Heavy weight machine on soil.
3. Livestock walking over the soil.
Soil compaction can result to decrease in crop production and increase in erosion of soil.
The purpose of the soil compaction is that large water pressure which is build up and causes soil liquefy in the time of earthquake.