The sentence begins with
Though, indicating the presence of two contrasting ideas.
The first part of the sentence talks about the town. We need an adjective for the town, which is described as scenically beautiful.
Sprawling means spreading out over a large area in an untidy or irregular way.
Desolate means lonely and uninhabited. The word
bucolic refers to the pleasant aspects of the countryside and country life. Therefore, it is the best option.
The second part of the sentence talks about Christine's feelings about the town. We know that it should express a sentiment opposite to that of the first part of the sentence, because of the
though at the beginning of the sentence. Since in the first part of the sentence, the town is praised as scenically beautiful, we must expect a negative comment about the town.
An
attractive backwater is a positive comment about the town, so it cannot be the correct choice. A backwater, which is a part of a river in which there is little or no current.
A
picaresque backwater does not make sense, because picaresque (not to be confused with picturesque, which means scenic) refers to a fictional work dealing with the adventures of a rough and dishonest but appealing hero.
A
cultural backwater is a place that exists in a state of cultural backwardness. It expresses a feeling opposite to that of "scenically beautiful".
Though the town was scenically beautiful, it was a cultural backwater.
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