The answer should be surface.
The right answer is Nutrients and water.
All unicellular organisms such as bacteria and fungi need water, a source of energy, a source of carbon, a source of nitrogen and mineral elements. These basic needs are sufficient to allow the nutrition of bacteria qualified as prototrophs. Some bacteria called auxotrophs require, in addition to basic needs, the presence of growth factors.
A tiltmeter monitors the earth's crust to determine if any uplift is occuring. Simply put, it measures the crust to see if the elevation has changed.
I believe your answer should be glacial drift
