Answer:
E. fluctuate rapidly on time scales as short as a few hours.
Explanation:
Quasars are defined as massive celestial object, emitting immense amounts of energy, and usually appearing as a star like image when viewed on a telescope. According to my research on Quasars, I can say that based on the information provided within the question they must be small because they fluctuate rapidly on time scales as short as a few hour.
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