Final answer:
The two primary reasons that justify a search incident to arrest exception are (1) the presence of weapons or evidence that could be destroyed and (2) the need to protect the safety of the arresting officer.
Step-by-step explanation:
The two primary reasons that justify a search incident to arrest exception are (1) the presence of weapons or evidence that could be destroyed and (2) the need to protect the safety of the arresting officer. When a person is being arrested, the police have the authority to search the area within the person's immediate control to ensure their safety and prevent the destruction of evidence. This exception allows the police to search for weapons or evidence without obtaining a search warrant.