What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? If Charles drinks water, then Linda is driving a car. If Charles drinks water, then Linda is driving a car. If Linda drives a car, then Charles is drinking water.
Charles is drinking water if and only if Linda is driving a car. Charles is drinking water if and only if Linda is driving a car. Linda is driving a car if and only if Charles is drinking water. Linda is driving a car if and only if Charles is drinking water.