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_15 for which if x_15 were a politician, then x_15 is climbing a mountain. For all x_15, x_15 will play a game or x_15 will not drive a car. For all x_15, x_15 will drive a car. For all x_15, x_15 is a politician or x_15 is an office clerk. For all x_15, if x_15 were an office clerk, then x_15 is climbing a mountain.
For all x_15, if x_15 drives a car, then x_15 is playing a game can be inferred via the universal rewriting rule. There is at least one x_15 for which x_15 will climb a mountain can be inferred via the existential disjunction elimination rule.