The independent clause is "WE ARE NOT EATING ON THE PATIO" the reason why, is because the second part of the sentence cannot stand on its own, due to the fact it has a because in it. because is a transition word.
C it makes the most sense
I believe the answer is C
In a story the setting of the time can appear regarding a moment the life of a personage, some year, period of the day or week, or a season, a month. In this text "1635, the evening..." show the relationship with timing of events.
The correct answer is Timing of events.