an excited electron falls to ground state emitting orange light. and even more excited electron falls. what color will not be exhibited, why?

The answer : orange light

The basic concept of quantum mechanics :
When an electrons in a certain excited state falls to ground state, a photon of orange light is emitted.
When two electrons in this excited state fall to ground state, two photons of orange light are emitted.
When three electrons in this excited state fall to ground state, three photons of orange light are emitted.
…… (and so on) ……
When n electrons in this excited state fall to ground state, n photons of orange light are emitted.

The even more excited electron will not emit any radiation with a wavelength longer than orange light. That means no orange or red light because the higher excitation state has a higher energy, and thus more energy, which means shorter wavelength emissions.