A police officer is at a crime scene and locates a footprint in a flowerbed near an open window. The window is examined closely and pry marks are discovered on the lower window sash and the window sill indicating forced entry. The police officer pointed out the evidence to the investigator who photographed the evidence and collected the footwear impression using a liquid footwear casting system. Who is required to testify in court to get the evidence admitted during the trial?

Read the following: (1) liz has become more responsive to her partner's advances since a really beautiful woman moved in next door; (2) unable to accept his desire for other young men, 15-year-old juan immerses himself into his studies; (3) shauntel tells people that her coworker mary dislikes her; though if she were honest, shauntel would realize that it is actually she who dislikes mary; (4) "ben's nasty; he's disgusting," says renee; but renee secretly finds ben attractive. describe the defense mechanism he or she is using.