According to historical linguistics, which of the following choi

According to historical linguistics, which of the following choices is not the cause of language changes?
A、social changes and contacts
B、Human evolution
C、cultural transmission
D、least effort principle
【正确答案】：B
【题目解析】：历史语言学主要研究了社会因素，文化因素以及省力原则对语言变化的影响。