The formation of new words by converting words of one class to a

The formation of new words by converting words of one class to another class is called（ ）.
A、prefixation
B、suffixation
C、acronymy
D、conversion
【正确答案】：D
【题目解析】：本题主要考查转类法。将一个词类的单词转换成另一个词类，由此形成新单词的方法被称为转类法。