Which of these is an example of the exchange principle?
A.Making casts of footprints at the crime scene
B.Taking photographs of the scene to be used later
C.Leaving markers to show the location of evidence
D.Leaving a strand of hair on a murder victim
Locard’s exchange principle says that, in the physical world, whenever perpetrators enter or leave a crime scene, they will leave something behind and take something with them.
