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.
He went to London and sold his plays, and since his style of writing was unique, so people were interested in him.
Explanation:
The nineteenth century was an era of great inventions in the united states. look at the list of inventions below and order them from most to least important (in your opinion). then explain why you ranked the top three inventions as most important. 1834: refrigerator invented by jacob perkins 1837: morse code invented by samuel morse 1853: elevator invented by elisha graves otis 1873: typewriter invented by christopher latham sholes 1876: telephone invented by alexander graham bell 1877: gramophone invented by thomas edison 1879: light bulb invented by thomas edison 1886: dishwasher invented by josephine cochran.
