What types of fingerprints will fluoresce under appropriate illumination?

The correct answer highlights that both natural latent fingerprints and some contaminants from the environment can fluoresce under appropriate illumination.

Natural latent fingerprints are deposits of sweat and oils from the skin, which can contain substances that fluoresce, especially when exposed to specific wavelengths of light. These natural substances can be enhanced using fluorescent powders or lighting techniques in forensic examinations, allowing latent prints to be visualized more clearly.

Contaminants from the environment, such as certain residues or materials that come into contact with the fingers, can also fluoresce. For example, substances like some types of inks, certain cleaning agents, or even biological materials can emit fluorescence under the right conditions.

The combination of these two elements — the natural compounds in latent prints and the environmental contaminants that may also exhibit fluorescence — justifies the choice indicating that both types may fluoresce under suitable lighting. This knowledge is crucial for forensic examiners in effectively locating and analyzing latent prints during investigations.