A Shift in the Position of an Emission Line of an Element

Multiple Choice

A shift in the position of an emission line of an element toward the red or blue is produced by ____.

A) atoms that become ionized
B) electrons that transfer from a high energy level to a low energy level
C) electrons that transfer from a low energy level to a high energy level
D) the intensity of agitation of atoms in a hot gas
E) the motion of an object toward or away from the observer