- **Loosely** is the word in question.
- **Verb**: These are action words (e.g., run, eat). "Loosely" isn’t performing an action here.
- **Adverb**: These modify verbs, adjectives, or other adverbs (e.g., quickly, very).
- ✔️ "Loosely" describes how the novel is based, modifying the verb "is based."
- **Noun**: These are people, places, things, or ideas (e.g., cat, happiness). "Loosely" doesn’t fit this category.
- **Adjective**: These describe nouns (e.g., big, blue). "Loosely" doesn’t describe a noun here.

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