We have to raise our prices because of the increase in the cost of_____ materials.
【正确答案】
D
【答案解析】解析:考查形容词辨析。primitive指“原始的,最初的”,如a primitive society(原始社会);rough指“(某物)粗糙的,(态度)粗暴的”;original“最初的,原作的”,如all original painting(原画),the original meaning of the word(单词的原始意义);raw指“未加工的”,如raw materials(原材料)。