Fact 1: Soil is formed by weathering. Fact 2: Soils are formed by breakdown of rock. Given the two facts above, _ is the breakdown of rock.?
Select from:
[i] Weathering.
[ii] mechanical.
[iii] salinity.
[iv] heat energy.
[v] dangerous.
[vi] cycles.
[vii] calcite.
[viii] started.
Answer:
[i]