第31题: [单项选择]The IPCC announcement three years ago that "most of the warming observed over the last 50 years is" ______. A. possibly due to human activities B. possibly because human activities C. due to likely human activities D. human activities likely attributable 参考答案:A 答案解析:[分析] 短语题型。
根据第二段第二句The IPCC announced in 2001 that “most of the warming ob served over the last