Multiple Choice
Of the following components,which are responsible for the main spectral emission lines found in an emission nebula?
A) Neutral helium,carbon,oxygen,and iron atoms
B) Ionized helium atoms and electrons
C) Protons,positrons,helium nuclei,and neutrinos
D) Hydrogen atoms,protons,and electrons
Correct Answer:
Verified
Correct Answer:
Verified
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