Canada has vast areas of wilderness from the Arctic north average winter temperatures a

问题补充：

Canada has vast areas of wilderness, from the Arctic north, average winter temperatures are usually -20 0C, to the border with the USA in the south, is said to be the longest border in the world not defended.

A. which, where

B. whose, which

C. where, where

D. where, which

答案：

A. which, where

B. whose, which

C. where, where

(答案→)D. where, which

解析：考查定语从句。句中where引导定语从句，先行词为the Arctic north，在从句中作地点状语；which引导非限定性定语从句，指代前面的事情。故选D。