Books are made paper while paper is mainly made wood.A. of; of B. from; from C. of; from

问题补充：

Books are made paper while paper is mainly made wood.

A. of; of B. from; from C. of; from

答案：

解析：句意：书是由纸制成的，而纸主要是由木头制成的。Be made of由…制成，从产品中能看得出原料；Be made from由…制成，从产品中不能看出原料。所以选C。