Answer:
The most likely to be a speakers purpose in the following statement is to express the opposite of what the speaker is saying.
Step-by-step explanation:
The statement: "It's a great place to have dinner...unless you like clean silverware, prompt service, and hot food", is, in fact, showing in a very sarcastic form the reality of the place that has dirty silverware, a terribly bad service and of course cold food to serve, therefore this place is nor the best place to have dinner at all.