Many of the earth’s plants and animals have already and several other species are endangered．
A. died away
B. died out
C. died down
D. died of
网友回答
A. died away
(答案→)B. died out
C. died down
D. died of
解析：短语辨析。 A．消失 B．灭绝 C．逐渐消失D．死于。句意：地球上的许多动物和指物已经灭绝，一些其它物种濒临灭绝。故选B。