Answer:
Hasty generalization fallacy.
Step-by-step explanation:
The hasty generalization fallacy is one type of fallacy where a person jumps to a conclusion in a hasty manner. There is no clear and calm, thinking-through process involved.
Based on the given statement that the speaker is "sick of working with the public", the speaker is drawing a conclusion that "people are just obnoxious". This is a hasty generalization fallacy as the speaker is making an assumptive conclusion from a biased perspective.
Thus, the correct answer is the hasty generalization fallacy.