单选题 ______ plastics, the machine is light in weight.
A. Made of B. Having made with
C. To make of D. To be made of

【正确答案】 A
【答案解析】[解析] made of由……材料做成，这是分词短语(被动态)作状语表示原因。to be made of表示将来，不表示现在。以being引导的现在分词短语常常省略being而只保留表语部分。