What is a characteristic of fingerprint residue?

Fingerprint residue is primarily composed of substances that are secreted by the skin, including a significant amount of moisture in the form of sweat, which is approximately 97% water. The remaining 3% is made up of fats, oils, and amino acids. This composition is crucial for understanding how fingerprints can be left behind on surfaces and how they can be processed for identification. When a person touches a surface, the moisture and other components from their skin transfer onto that surface, creating a latent fingerprint.

The amount of water in fingerprint residue is important as it helps in developing techniques for lifting and analyzing these prints. The presence of fats and oils plays a significant role in how fingerprints can be visualized using various chemical processes during forensic investigations.

The incorrect options either misrepresent the composition of fingerprint residue or omit key components critical to understanding it. For instance, stating that fingerprint residue consists of 50% water significantly underestimates the actual moisture content. Additionally, claiming it contains no fats or oils disregards essential constituents that contribute to the uniqueness of each fingerprint. Lastly, suggesting that fingermarks are mainly composed of dust particles overlooks the biological nature of the residue, which is vital for forensic analysis and identification procedures.