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【单选题】Color is very important to most animals for it helps them to get along in the world. Color (21) to make an animal difficult for its enemies to (22) . Many animals match their (23) so well that as lon...
A.
Even if
B.
Unless
C.
However
D.
As long as
【单选题】Vater壶腹癌（）。
A.
胆囊肿大，Murphy征阳性
B.
胆囊肿大，无触痛
C.
胆囊不大，坚硬
D.
胆囊肿大，肝大结节感
E.
胆囊肿大，黄疸，十二指肠反流征