Answer:
D.Nos vemos en el restaurante
Explanation:
a.See you later
b.just for a while
c.sure
Entonces, ¿en qué quedamos? means "So What are we gonna do?"
Nos vemos en el restaurante means ¨"I ll meet you in the restaurant"
This might not make sense but is something would say if someone asks me that.(my mother tongue is spanish)