Answer:
an unsolved mystery
a story based on historical events
a love story
an action-packed story
a story about the future
Explanation:
I would check all of these, this is a matter of personal preference.
The main thing that this question is asking is which sentence does not have a formal tone. A formal tone for research writing usually means using more professional (instead of casual, everyday) language and free of your own opinions.
This means choice D is inappropriate because it is opinionated. Using "I think" is not formal tone.
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Answer: D) I think one of the most frustrating things about owning a cat is that they don't obey many commands.
it gives your average person a sense of hope
To entertain. The books are literally a fantasy series. I suppose it also helped her through her depression and such, but her actual purpose was to entertain and teach some morals suck as the importance of friendship.