Answer:   INVOKE - Use the INVOKE step to request a service within a flow. You can use the INVOKE step to:

􀂄 Invoke any type of service, including other flow services and Web service connectors.

􀂄 Invoke any service for which the caller of the current flow has access rights on the local webMethods Integration Server.

􀂄 Invoke built‐in services and services on other webMethods Integration Servers.

􀂄 Invoke flow services recursively (that is, a flow service that calls itself). If you use a flow service recursively, bear in mind that you must provide a means to end the recursion.

􀂄 Invoke any service, validating its input and/or output.