Only when he was told that his precious stone was but an artificial gem did the old man realize that...

参考答案: D

参考解析: 本句意思是：只有当别人告诉他那宝贵的钻石其实是一枚人造的宝石，他才意识到他被人骗了差不多10万元人民币。句中artificial意为“人造的”，如：This food contains no artificial flavorings.这种食品不含人工调味品。四个选项中superficial意为“表面的，肤浅的”，例如：The book shows only a superficial understanding of the historical context．这部书表现出对历史背景肤浅的理解。custommade意为“定做的”，如：Furniture can also be custom-made to suit your own requirements.你也可以按照自己的要求定制家具。ready -mad。意为“现成的”，如：We rely quite a bit on ready-made meals一they are so convenient.我们很是依赖现成食物——它们真的很方便。man-made意为“人造的”，如：Man-made and natural disasters have disrupted the Government's economic plans.天灾人祸打乱了政府的经济计划。只有选项D同句中画线词语含义接近。