单选题
Human choice, not the intrinsic content of science, determines the outcome and scientists, as human beings, therefore have a special responsibility to provide council rooted in ______.(2009年北京航空航天大学考博试题)
【正确答案】
C
【答案解析】解析：四个选项的意思分别是：expiration期满，到期：explanation解释，说明；expertise专家意见，专门技术；expenditure支出，消耗，根据句子意思可知，正确答案是C选项。如：His field of expertise was steroids．(他的专业领域是甾族化合物。)