In 1895 Lines Were Observed in the Spectrum of Uranium

Multiple Choice

In 1895 lines were observed in the spectrum of uranium ore identical to those of helium in the spectrum of the Sun.Which of the following produced the lines in the helium spectrum?

A) excited electrons jumping to a higher energy level
B) excited electrons dropping to a lower energy level
C) excited protons jumping to a higher energy level
D) excited protons dropping to a lower energy level
E) none of the above