Final answer:
Local law enforcement is the most likely entity to initiate a complaint investigation in response to a hotline call concerning alleged abuse or neglect. The correct option is (b).
Step-by-step explanation:
If an elderly person suffers abuse or neglect, a hotline call can be made to report the incident. In response to such a call, several entities may be involved in initiating a complaint investigation.
These may include local law enforcement, the state survey agency, or the resident's family.
Of the options provided, the most likely entity to initiate a complaint investigation would be Local law enforcement. They have the authority and expertise to investigate allegations of abuse or neglect.