Which statement is true? a. When a method call is made, the called method must know how to return to its caller, so the return address is pushed onto the program execution stack.
b. Stacks support recursive method calls in the same manner as conventional, nonrecursive method calls.
c. The program execution stack contains the space created for a method's global variables on each invocation of that method during a program's execution.
d. When a method returns to its caller, the memory for that method's local variables is popped off the stack and those variables are no longer known to the program.