Assume GNU Prolog (gprolog) has been loaded with the following facts:

happy(bob).
happy(cat).
happy(day).
happy(dog).

And the user enters a query,

| ?- happy(X).

Please show how GNU Prolog's interactive mode behaves. Specifically, please show:

A) How GNU Prolog responds to this query and

B) What the user must enter next to make GNU Prolog display all possible answers for X.