sc大全中的一題

[stupidboy93]

After a few weeks’ experience, apprentice jewelers can usually begin to [sub]discriminate[/sub], though not with absolute certainty, [sub]genuine diamonds from imitation diamonds[/sub].
(A) genuine diamonds from imitation diamonds
(B) genuine diamonds apart from imitations
(C) between genuine diamonds and imitation diamonds
(D) among genuine diamonds and imitation diamonds
(E) whether diamonds are imitation or genuine

為何這題答案會是c 為何a不行ㄋ？ 謝謝回答！

[Pufa]

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