How is evidence defined in a criminal investigation?

Evidence in a criminal investigation is defined as any material that may aid in determining the truth of what occurred during a crime. This definition encompasses a broad range of items and information that can contribute to building a case and establishing facts. Evidence can include physical objects, documents, digital data, and also includes witness testimonies. The key aspect of this definition is its inclusivity; it recognizes that anything that helps clarify the circumstances of a crime, regardless of its form, is relevant.

In contrast, the other options focus on narrower interpretations. Visible items found at the scene are certainly a type of evidence, but they do not encompass the entire scope of what is considered evidence. Testimonies from witnesses are crucial, but they are just one subset of evidence rather than a comprehensive definition. Animal footprints can provide important information in certain investigations, but again, they represent only a specific instance of evidence rather than a complete definition. Therefore, "any material that may aid in determining the truth" is the most accurate and comprehensive understanding of evidence in this context.