What type of samples should be collected from suspects for analysis?

The correct choice emphasizes the importance of collecting handwriting samples from suspects for analysis. Handwriting samples can be critical in forensic investigations, as they allow forensic experts to compare the writing of a suspect to other documents, particularly if a note or other written evidence is involved in a case. Handwriting analysis can reveal unique characteristics of a person's writing style, which may help establish the identity of the writer.

Handwriting samples can be particularly useful when there are uncertainties about authorship, and they play a significant role in criminal investigations, especially in cases of fraud, forgery, or any situation involving written threats. This kind of analysis provides insights that can corroborate other evidence or lead to new avenues of investigation.

Other sample types, while important in various contexts, serve different purposes. Fingerprint samples are essential for identifying individuals at crime scenes, physical evidence samples can include materials like hair or fibers that link suspects to crimes, and digital device samples analyze electronic evidence. Each type of sample has its relevance depending on the specifics of a case, but handwriting samples play a unique role in linking suspects to written materials.