The word liquor once meant liquid, but now means alcoholic drink

The word liquor once meant liquid, but now means alcoholic drink. This is an example _____ of word-meaning.
A、extension
B、narrowing
C、transfer
D、degradation
【正确答案】：B
【题目解析】：从题干看，这时关于词义变化的题。liquor 从液体到酒精饮料，意义缩小了，因此B为正确答案。