Blood evidence may include which of the following on upholstery or carpet?

Blood evidence on upholstery or carpet predominantly manifests as pooled blood, which is defined as large quantities of blood that collect in a specific area. This form of evidence is significant because it can help investigators reconstruct the events that occurred, analyze the possible movements of individuals involved, and determine the severity of the injury. The condition of the pooled blood, including aspects such as its size, shape, and distribution, can provide critical insights into the circumstances surrounding the crime.

In contrast, footprints are a type of evidence but do not directly pertain to blood. Gunshot residues relate to the discharge of a firearm and do not include blood evidence. Electronic records, while important for investigations, do not pertain to physical evidence found at a crime scene in the context of blood on carpets or upholstery. Thus, pooled blood stands out as the accurate choice related to blood evidence.