A bilingual speaker often uses two languages alternatively durin

A bilingual speaker often uses two languages alternatively during a conversation with another bilingual speaker, a speech situation known as ______.
A、discourse role-switching
B、activity role-switching
C、social role-switching
D、code-switching
【正确答案】：D
【题目解析】：根据题干中的“uses two languages alternatively”和code-switching的定义“语码转换是指说话者或写作者从一种语言或语言变体转用另一种语言或语言变体的现象。”可知答案选D。