17. Insulin is produced and released by specialized cells in the pancreas ______ glucose reaches a certain
concentration in the bloodstream.
(A) whichever
(B) whenever
(C) however
(D) moreover
(E) whatever
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統計: A(0), B(8), C(0), D(0), E(0) #3306549
統計: A(0), B(8), C(0), D(0), E(0) #3306549