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Question
Which of these is true of planetary nebulae?A) They are expelled by the most massive stars in their final stages before supernova.
B) They are rings of material around protostars that will accrete into planets in time.
C) They are ejected envelopes surrounding a highly evolved low-mass star.
D) They are the envelopes that form when blue stragglers merge.
E) They are the material which causes the eclipses in eclipsing binary systems.
Answer
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