Princeton Review Gen Chem Question

[MissionStanford]

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Which of the following colors would appear as a bright band in an emission spectrum of a yellow sodium vapor lamp?

The answer is:
Yellow, indicating a greater wavelength than ultraviolet light.

What I don't get is, why would yellow be emitted just because the sodium vapor is yellow? Doesn't the emission spectrum have to do with electron excitation and release of photons as the electrons move back down energy levels?

 

[Singhp03]

think whats happening is this:
emitted photons correspond to frequency and energy at 'yellow' visible range bc outer electrons,bc they are easiest to excite, fall back to ground state with lower energy(visible) than inner electrons which if excited take much more energy and as a result emit photons, most probably, in UV range.