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_7, if x_7 were a musician, then x_7 is poor. For all x_7, if x_7 climbs a mountain, then x_7 is poor. For all x_7, x_7 is a musician or x_7 will listen to a song. For all x_7, if x_7 listens to a song, then x_7 is climbing a mountain. For all x_7, x_7 is not poor or x_7 is a taxi driver.
For all x_7, if x_7 listens to a song, then x_7 is poor can be inferred via the universal transitivity rule.