Which of the following definitions applies to permafrost?

A. A long, narrow, deep inlet of the sea between steep slopes.

B. Permanently frozen subsoil, occurring in perennially frigid areas.

C. A treeless area between the icecap and the tree line of Arctic regions, having permanently frozen subsoil and supporting low-growing vegetation such as lichens, mosses, and stunted shrubs.

D. A subarctic, evergreen coniferous forest of northern Eurasia located just south of the tundra and dominated by firs and spruces