Choose the word or set of words that, when inserted in the sentence, best fits the meaning of the sentence as a whole. 

Many forests in the southern region of the continent are ------- plant and animal diversity, partly because they never suffered the onslaught of glaciers that wiped out flora and fauna in northern forests long ago.

1.   rich in
2.   devoid of
3.   dependent on
4.   protected from
5.   conflicted about