Which of the following defines permafrost?
A. Permanently frozen subsoil
B. long, narrow arms of the sea bordered by steep cliffs
C. a subarctic biome containing wide swaths of evergreen, coniferous forests
D. None of the above

A

Explanation:Perma is a root that means permanent and Frost is well,frost

The answer is A

Explanation:

Because Permafrost is soil that is under the top soil which is permanently frozen. Permafrost is soil that is under the topsoil, the subsoil is permanently frozen.

And its nothing to do with the sea bordered by steep cliffs, because that has nothing to do with frost or frozen.

And a subarctic biome is parts of land that are frozen through out the year but melt rarely.

c. seafloor spreading occurs.

d. crust becomes molten rock.

e. denser plates slide under lighter plates.