[单选题]The passage suggests that the early shops for making tools were ______.

正确答案 ：A

not very sophisticated

解析：解析：本题的依据句是“At first，these articles were whittled with a knife，but when pioneer craftsmen set up their primitive shops most of them were fashioned on a lathe--a machine which holds an object and rotates it while it is being shaped by a tool.”在这里，A选项的not very sophisticated 意思为“并不复杂，是简单的”，对应原文中的primitive(原始的，简单的)。其他选项的内容属于无关信息。

[单选题]Wood carving refers to the art of creating or decorating objects of wood by carving with a sharp, hand-held tool. This form. of art has a history of over 1,000 years and a unique artistic style. The following is some introduction about wood carving in America.

正确答案 ：D

arts and crafts

解析：解析：木雕属于一种艺术，也是一种手艺。其他选项的内容在本文中没有涉及，属于无关信息。

[单选题]Science is still ______ of the causes of many kinds of cancer.

正确答案 ：A

ignorant

解析：解析：ignorant可以指“无学识的，愚昧的”，还指“不知道的”；unconscious意为“失去知觉的，不省人事的；无意识的”；conscious意为“有知觉的，意识到的”；informed意为“获悉，告知”。

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