Answer:
Ethnocentrism
Explanation:
What's professor Zhang is doing is a clear case of ethnocentrism. this is given that she's using the standard and customs of the place where she's from to judge how people should behave in a different culture. ethnocentrism gives one the belief that his or her culture is better than that of others. such a word is often used where issues of ethnicity of concern.
Since people from her culture do not go on a first-name basis, she believes that wherever she is no one should call her by her first name else the person is disrespectful.