"Where the people are" doesn't simply mean "where a large number of people live". It also has connotations of "where it's happening", as in "where people are coming together (right now)".
But my point is really that speaking of the correct answer with a question as vague and open to interpretation as this one is absurd.
Indeed, I pattern matched (a) as the correct answer too, but on reflection on the content of the words and what it would all actually mean, I think that (a) is a bad answer. If we aren't careful we'll train our AIs to be good at giving incorrect, pat answers to inadequately thought out questions.
Training an LLM on a ton of multiple choice questions doesn't "infect it" like you're thinking. The tokens capture the fact it's a multiple choice question, and the LLM eventually captures the nuance of textual entailment as a common form of multiple choice question.
In a more natural conversational setting, you'd get a different answer:
But my point is really that speaking of the correct answer with a question as vague and open to interpretation as this one is absurd.