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: Charles is not climbing a mountain. For all z, z will drive a car if and only if z will climb a mountain. For all z, if z climbs a mountain, then z is driving a car.
For all z, if z drives a car, then z is climbing a mountain can be inferred via the universal biconditional elimination rule. For all z, if z climbs a mountain, then z is driving a car can be inferred via the universal biconditional elimination rule.