Which one of these implementations will allow a process to reply back to the calling process?

Which one of these implementations will allow a process to reply back to the calling process?

A.
a Receive task followed by a Send task that implements a Service call to the calling process

B.
a Send task with Conversation set to Initiates In its implementation

C.
a Service task that implements a Process Call to the calling process

D.
a Receive task with Conversation set to Initiates followed by a Send task with conversation set
Continues

Explanation: