Clarity on intended usage for classes within category

[Jthomas54]

This specifically pertains to: API Activity and Entity Management for the Audit category.

We are looking to implement some auditing and are considering storing our events in accordance with the OCSF. Part of this is determining what is the proper class to store audit event as.

Looking at API Activity and Entity Management, it isn't clear what the difference is between these two are; or rather the ideal use case for the class is. The definitions, in general, have the same fields so why is there a distinction between the two events? We have a SoA, so my guess is that we should use API Activity, but Entity Management also calls out microservices as a use case.