When is the operation executing, suspended and active?
(a) An operation is executing when some process is actually running its code
(b) An operation is suspended when it sends a synchronous message and it is waiting for the message to return
(c) An operation is active when it is either executing or suspended
(d) All of the mentioned
The question was asked in unit test.
This is a very interesting question from UML Sequence Diagrams in portion Unified Modelling Language of Software Architecture