The option that would best contrast the real and the model atoms is letter "D. model of an atom is not as small as an actual atom". The size of an atom is said to be no more than 0.1 to 0.5 nanometers. The models are used to proper illustrate the atom's physical attributes. That is why, it needs to be bigger in size.
Answer: As a result, each excited electron in an atom emits a photon of a specific wavelength. To put it another way, each excited noble gas emits a distinct hue of light. This is a reddish-orange neon light.