ANSWER:
Subsidence is the "lowering of the land-surface elevation" from changes that take place underground is true.
Step-by-step explanation:
- Land subsidence takes place because of the changes that take place underground. These changes impact the elevation and level of land causing it to become low.
- The most common causes of subsidence include oil drilling, pumping water and also the "dissolution of limestone aquifers".
- Subsidence is not considered to be good for land and has many adverse impacts on the land.
- Subsidence causes damage to roads and highways. It also results in damaged buildings and well casings.
- Subsidence also brings with it problems associated with flooding because a small change in land gradient can adversely impact the drainage system.