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.
Maturity is when you start to see things for what it is in life. It is when you gain wisdom and someone who is mature is someone who doesn’t “cry over spilt milk.” It occurs when someone endures so much in life and they now are mature enough for physiological gain.
Answer:
One of your problems would be thirst and overheating
Explanation:
