Latent prints require observation by which method?

• A. Direct bright light
• B. Field testing with dogs
• C. Visual inspection only
• D. Observing with powder or chemical development

Answer: (D)

Latent fingerprints are invisible to the naked eye because they’re made of tiny residues of sweat and oils left on a surface. To observe them, you need to render them visible through enhancement techniques such as powder dusting or chemical development, which either adhere to the residue or react with it to create a visible print. Visual inspection alone won’t reveal these impressions since nothing noticeable is present without the development step, and field-detection dogs aren’t used to observe fingerprints—dogs detect odors, not the prints themselves.