Which Very Significant Fact Concerning the Spectra Produced by Hot

Multiple Choice

Which very significant fact concerning the spectra produced by hot gases, such as elements heated on the solar surface (Fraunhofer, with the solar spectrum) or in a flame (Bunsen and Kirchhoff, with laboratory spectra) , was discovered in the 1800s?

A) Each chemical element produces its own characteristic pattern of spectral lines that remains fixed as the temperature increases.
B) Chemical elements emit spectral lines that move continuously toward the blue end of the spectrum as the gas temperature increases.
C) The higher the temperature, the greater the redshift of the emitted spectral lines.
D) Every chemical element produces the same set of spectral emission or absorption lines as every other chemical element, but their relative emission intensities differ.