In the given sentence, the bulwark is the noun as it represents a defensive wall which is a thing.
Option B is the correct answer.
The sentence is a meaningful line that consists of verbs, adverbs, adjectives, nouns, and many more.
Nouns are the words that constitute a thing, place, person, or idea. They are bifurcated into two types, singular, and plural nouns. The word bulwark used in the sentence is for referring to a wall or something that creates a defense for the city.
Therefore, the word bulwark is a noun used in the provided sentence.
Learn more about the nouns in the related link:
https://brainly.com/question/134274
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