Which type of bloodstain is formed when blood is transferred from one surface to another?

The formation of a transfer bloodstain occurs when blood is moved from a surface—such as a victim's body—to another surface, typically through contact. This type of bloodstain often retains the pattern or shape of the object that made the transfer. For instance, if a bloody hand touches a wall, it may leave an imprint that resembles a handprint. This is a crucial aspect of crime scene investigation, as analyzing these stains can provide valuable evidence about the events that transpired.

In contrast, impact bloodstains are generated when blood is projected as a result of a force or impact, such as a gunshot or a blunt force trauma, resulting in splatter patterns. Passive bloodstains are those created by the force of gravity, like drops falling onto a surface, while exsanguination refers to the act of blood loss which can lead to pooling but is not a specific type of bloodstain. Thus, the specificity of how blood is transferred directly supports the selection of transfer bloodstain as the correct answer.