A physician may use technical terms when he is talking with his

A physician may use technical terms when he is talking with his fellow physicians, but he may use ordinary vocabulary when he is talking to his patients. This is an example of ______.
A、dialect
B、register
C、Speech Community
D、Idiolect
【正确答案】：B
【题目解析】：语域指的是语言的功能变体，即因情景语境的变化而产生的语言变化形式。