16. Which of the following respiratory systems is not closely associated with a blood supply?
(A) the tracheal system of an insect
(B) the skin of an earthworm
(C) the gills of fishes
(D) the skin of an amphibian
(E) the lungs of a vertebrate
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統計: A(61), B(11), C(3), D(7), E(5) #1321137
統計: A(61), B(11), C(3), D(7), E(5) #1321137