How do prepositions function in a sentence

the correct answer is d. in john paston's letter written friday, 14, 1476, he expresses his fear that he may have to go to war.

indeed, although the black death was ravaging europe, the pastons were relatively safe from it due to their social status as they were part of the landed gentry. it is clear that the vast majority of the victims of the pandemic were the poor. the reason why he is weary of having to go to war is because at the particular time england was also devastated by the war of the roses and paston, being a courtesan was inevitably involved.