There are generally two major factors that cause changes in mean

There are generally two major factors that cause changes in meaning，extra-linguistic factors and （ ） factors within the language system.
A、functional
B、external
C、meaningful
D、internal
【正确答案】：D
【题目解析】：引起词义变化的因素一般有两个，即非语言因素和语言系统内部因素。