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 x_6: Q(x_6) or S_1(x_6). forall x_6: S_1(x_6) -> P_3(x_6). forall x_6: Q(x_6) -> P_3(x_6). exists x_6: U(x_6).
forall x_6: P_3(x_6) can be inferred via the universal disjunction elimination rule.