Any programs that are still running will be in the call stack.
However, your question implies that the CALL to A was done from a command line and that A had ended, therefore returning to the command line. Any program that ends is removed from the call stack — that’s one of the effects of ending. It doesn’t matter if the program ends with *INLR on or off. The LR indicator has no connection to the removal of a call stack entry.
Your description directly implies that none of your programs are still running, so none can be on the call stack.
Your question is probably about whether or not any activation group still exists. The AC2 activation group has been activated and it remains. No program from AC2 is on the call stack. If program C is called again, the AC2 activation group will not have to be recreated by the system.