Officer Green Has Been Dispatched to a Hotel That Is

Officer Green has been dispatched to a hotel that is the scene of a shooting. He sees the following items with potential evidentiary value scattered about the scene:
•6 shell casings that are scattered around the room
•A dirty towel on the floor near the bullets What should Officer Green do first?

A) Place each item of evidence in a plastic evidence bag.
B) Cordon off the crime scene and restrict access to area.
C) Photograph and diagram the crime scene.
D) Call housekeeping for assistance.