Final answer:
The information required to determine when Paul Kinkaid showed up at Sergio's door is not provided in the excerpts, so an accurate answer cannot be given without additional context.
Step-by-step explanation:
The excerpts provided do not include direct information about a character named Paul Kinkaid or the specific time he showed up at Sergio's door. Given that the information is absent, there's no basis to accurately answer the question with options A) 6:00 PM, B) 8:00 PM, C) 10:00 PM, or D) Midnight from the provided context. To determine the correct time Paul Kinkaid appeared at Sergio's door, the specific text or story where this event takes place would need to be referenced directly.