Who knows why the answer to 885-sec21-22 is (E)

nlyang

Unlike most warbler species, the male and female blue-winged warbler are very difficult to tell apart.

>>>> I chose (B), which I considered more concise than (E)...But how come the answer is (E) ?? Could anyone explain this to me, please?

chenmoon

A：unlike前后一个是群体（species），一个是个体（warbler），所以是不对的。
B：unlike前后一个是species，一个是gender，没法比较。
E中unlike前后都是群体性质的，所以正确

nlyang

Thank you very much for your reply