The process by which a word which originally had a specialized meaning has now become generalized is_______of word-meaning.
A、transfer
B、elevation
C、narrowing
D、extension
【正确答案】：D
【题目解析】：本题考查对于词义变化类型的变化，extension 和narrowing 是一对概念，elevation和degradation 是一对概念。根据定义内容和题干信息，D为答案 。
