Are you just asking questions, or are you asking some one to write an essay for you?
The answer is: [D]:
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They are often used to combine choppy sentences.
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Conjunctions are often used to combine choppy sentences.
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Note: The questions asks about CONJUNCTIONS —NOT about "contractions".
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Choice "A" is incorrect. They are not used to combine two or more LONG sentences. If sentences are already long, then do not need to be combined with a conjunction.
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Choice: "B" is incorrect. To the contrary, the use of conjunctions actually makes sentences longer.
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Choice "C" is incorrect. To the contrary, the use of conjunctions should be used (appropriately, of course) in essays. The use of "contractions" should not be used in essays or formal writing.
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Choice "D" is correct. They are often used to combine choppy sentences for better reading and engagement.
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The electromagnetic wave is self propagating, what I mean by that is, an electric field generates a magnetic field at 90 degree phase angle, and the magnetic wave you get as a result generates the electric wave at the same phase angle. The interchange of electric to magnetic and vice versa continues and lets the electromagnetic waves to travel without any medium. Quite interesting, really!
Belief in the supernatural.
A main point of the Romantic era was the idea of intense emotional expression and the individual self, however it also dealt with an interest in supernatural interest and mysticism. There is a lot of influence from greek and roman mythology and the power of supernatural forces, so this makes the most sense.
that would imply the fact that he made history with his LAWS of physics so the answer is LAW