Which information is essential to verify the caller's borough?

To verify the caller's borough, utilizing the map alongside ANI (Automatic Number Identification) and ALI (Automatic Location Information) is essential. This combination provides vital geographical context and specific location data associated with the call being received. ANI gives the telephone number of the caller, while ALI provides the address and information related to that number, including its geographical area. When these two systems work together, they can pinpoint the caller’s location, allowing the technician to determine the borough from which the call originated.

In contrast, Caller ID solely provides the number, which does not guarantee accuracy regarding location information. Incident details can provide context about the call but don’t help establish where the caller is located. Similarly, an alarm code might indicate a triggered event at a specific business or residence but does not verify the caller's borough. Therefore, B is the correct choice as it encompasses the relevant and accurate information needed to ascertain the borough of the caller.