Question: In a CAMEL environment, which entity generates an Interface to notify the gsmSCF of a supplementary service invocation?
Option 1: Home Location Register (HLR)
Option 2: Visitor Location Register (VLR)
Option 3: Mobile Switching Centre (MSC)
Option 4: Gateway Mobile Switching Centre (GMSC)
Explanation: In the context of CAMEL, when a supplementary service is invoked, the entity responsible for notifying the gsmSCF is the one directly handling the call's switching functionality. The Mobile Switching Centre (MSC) is the core component that manages calls and supplementary services within the mobile network, making it the logical generator of such notifications to the gsmSCF for customized logic application.