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Question
In what sense are the quasars "quasi-stellar"?A) Their energy production is hydrogen-helium fusion, like main-sequence stars.
B) They are upscale versions of O stars, yet hundreds of times more massive.
C) Their luminosity comes from the millions of supergiants that compose them.
D) Their spectra are like those of ordinary stars.
E) In short time exposures, their images looked stellar.
Answer
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