The formal discussion<span> is very correct and serious, rather than relaxed and friendly, and it is used especially in official situations.</span>
Topics that are best suited for formal discussion are:
scientific discovery, literary analysis and medical diagnosis.
I Have waited nearly an hour
After reading through your question, I have come to the conclusion that the answer might be paragraph 3. I’m not totally sure though.
I would choose either c or d, but c seems more logical to me, given the author is stating the visitor's purpose through figurative language, I would assume they would have a more metaphorical purpose to their cause.
