When Astronomers Look for Evidence of Hydrogen Gas in the Spectra

Multiple Choice

When astronomers look for evidence of hydrogen gas in the spectra of the Sun,the planets,and nearby stars,the positions of the spectral features or "lines" due to hydrogen

A) are in a very different pattern,depending on the location of the planet or star,and are reproduced only with difficulty in the laboratory.
B) are always in the same pattern,characteristic of hydrogen gas,as seen in the laboratory.
C) change systematically,depending on the distance from the source,starting with a laboratory pattern.
D) are in the same pattern for solar and planetary sources but are very different for stars at larger distances because of absorption of light by the interstellar matter.