Give reason : the atom of the element produce more than one spectral line.

answer:

when atoms are excited they emit light of certain wavelengths which correspond to  different  colors. each  element produces  a unique set of  spectral lines. since no two  elements  emit the same  spectral lines,  elements  can be identified by their line spectrum.

it’s previous models   because when i picked that son of a gun’s answer it was wrong look for previous models because they might make it a different letter