Final answer:
Effective Communication is essential to a successful homicide unit according to the FBI Law Enforcement Bulletin. The correct option is (a).
Step-by-step explanation:
According to the FBI Law Enforcement Bulletin, one of the essential factors for a successful homicide unit is Effective Communication.
Effective communication within the unit ensures that information is quickly and accurately shared among team members, which helps them collaborate effectively in solving cases.
It also helps establish clear lines of communication with other law enforcement agencies and the community, leading to more successful investigations.