42. An oil-water mixture works as an insecticidal spray against mosquitoes and other insects because it _____.
(A)blocks the openings into the tracheal system
(B)interferes with gas exchange across the capillaries
(C) clogs their bronchi
(D) prevents gases from leaving the atmosphere
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統計: 尚無統計資料
統計: 尚無統計資料