Answer:
The host answers the guest with brief responses during the party because The host realizes the guest is not open-minded
Step-by-step explanation:
The third option is the one that best explains the reason why the host answers the guest with brief responses during the party, the other options do not seem to fit with the story where the host interacts with the guests and reacts according to how they are, there is no point in giving long explanations to someone who does not really care about them.