Multiple Choice
A planetary nebula is:
A) a contracting spherical cloud of gas surrounding a newly formed star, in which planets are forming.
B) the expanding nebula formed by the supernova explosion of a massive star.
C) an expanding gas shell surrounding a hot, white dwarf star.
D) a disk-shaped nebula of dust and gas from which planets will eventually form, easily photographed around relatively young stars.
Correct Answer:

Verified
Correct Answer:
Verified
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