113. Most of the area is covered by woods, where bird species are so _____ that it is a paradise for birdwatchers.
(A) durable
(B) private
(C) realistic
(D) numerous

該地區大部分被樹林覆蓋，鳥類種類眾多，是觀鳥者的天堂。（A）耐用（B）私有（C）現實（D）眾多。