The correct answer is C. Emission spectra.
When a metal is heated in a flame, the electrons absorb energy and jump to higher energy states. On coming back to the lower energy state, they emit light. This light is emitted in a specific wavelength, which corresponds to the energy difference between the two energy states. This wavelength can be observed in an emission spectrum.
A Raman spectrum is a type of spectrum that is produced by scattering of light by a material. The scattered light has a different wavelength than the incident light, and this wavelength difference is related to the vibrational energy of the material.
An absorption spectrum is a type of spectrum that is produced when light passes through a material. The material absorbs some of the light, and the amount of absorption is related to the wavelength of the light.
Fluorescence is a type of emission that occurs when a material absorbs light and then emits light of a longer wavelength. The wavelength of the emitted light is related to the energy difference between the two energy states.
In conclusion, the correct answer is C. Emission spectra.