Which statement describes using a Service Call control from the BPM Ul toolkit to invoke a service flow?

Which statement describes using a Service Call control from the BPM Ul toolkit to invoke a service flow?
A . It is used to invoke a service without having to use boundary events and has an input and output variable with on load, on invoked, on result, on error events. It can be placed in client side human service coach page or inside coach view.
B . A Service flow which has an input and output variable and a service task activity inside it calling an implementation service.
C . It is used to invoke a service that returns the data displayed in the table, never bound to variable, with on load, on service data loaded, on service data error events. It can be placed in client side human service coach page or inside coach view.
D . It is coupled with the human service in which it is used. It is created in the library area where User Interface library items are stored.

Answer: B