单选题 The question was discarded, because it was ambiguous.

【正确答案】 C
【答案解析】画线词ambiguous.的意思是:“模糊的,含糊的。”正确答案为C。辨义:A.incorrect不正确、错误的;B.biased有偏见的;C.vague模糊的;D.dull枯燥的。