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: ~S_16(a_16). q. forall x_16: S(x_16) <-> S_16(x_16). S(a_16) <-> q_7.
~S_16(a_16) and q can be inferred via the conjunction rule. q and ~S_16(a_16) can be inferred via the conjunction rule. S(a_16) -> q_7 can be inferred via the biconditional elimination rule. q_7 -> S(a_16) can be inferred via the biconditional elimination rule. forall x_16: S(x_16) -> S_16(x_16) can be inferred via the universal biconditional elimination rule. forall x_16: S_16(x_16) -> S(x_16) can be inferred via the universal biconditional elimination rule.