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: For all x_15, if x_15 climbs a mountain, then x_15 is not making tea. For all x_15, if x_15 were poor, then x_15 is climbing a mountain. For all x_15, x_15 will take a plane and x_15 will play a game. For all x_15, if x_15 takes a plane, then x_15 is an artist. For all x_15, if x_15 were an artist, then x_15 is making tea.
For all x_15, if x_15 takes a plane, then x_15 is making tea can be inferred via the universal transitivity rule. For all x_15, x_15 will take a plane can be inferred via the universal simplification rule. For all x_15, x_15 will play a game can be inferred via the universal simplification rule.