Answer:
Elderspeak speech style
Explanation:
Concept of Elder Speak
Elderspeak is a form speaking style in which the speaker speaks slowly with a very simplified vocabulary. The young speaker normally repeats keywords and uses passionate words to talk to the elder. Elderspeak can be used to communicate with people having a mental illness and some old people find elderspeak offensive.
What made the scenario an elderspeak;
The waitress used the ederspeak speech style.