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: There is at least one x_8 for which x_8 will drink water if and only if x_8 will drive a car. For all x_8, x_8 will not play tennis. For all x_8, if x_8 drives a car, then x_8 is playing tennis.
For all x_8, x_8 will not drive a car can be inferred via the universal modus tollens rule. There is at least one x_8 for which if x_8 drinks water, then x_8 is driving a car can be inferred via the existential biconditional elimination rule. There is at least one x_8 for which if x_8 drives a car, then x_8 is drinking water can be inferred via the existential biconditional elimination rule.