What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Name the inference rule being used: forall y_4: S(y_4) -> P(y_4). forall y_4: P(y_4) <-> W(y_4). forall y_4: P(y_4) -> S(y_4). forall y_4: ~S(y_4). exists y_4: P(y_4) -> W(y_4).
forall y_4: ~P(y_4) can be inferred via the universal modus tollens rule. exists y_4: S(y_4) -> W(y_4) can be inferred via the existential transitivity rule. forall y_4: S(y_4) <-> P(y_4) can be inferred via the universal biconditional introduction rule. forall y_4: P(y_4) <-> S(y_4) can be inferred via the universal biconditional introduction rule. forall y_4: P(y_4) -> W(y_4) can be inferred via the universal biconditional elimination rule. forall y_4: W(y_4) -> P(y_4) can be inferred via the universal biconditional elimination rule.