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: p_16 -> s. s -> r. p_16 <-> q_16. r -> q_16.
p_16 -> r can be inferred via the transitivity rule. s -> q_16 can be inferred via the transitivity rule. p_16 -> q_16 can be inferred via the biconditional elimination rule. q_16 -> p_16 can be inferred via the biconditional elimination rule.