To teach a tiger to jump through a flaming hoop, the tiger i…

To teach a tiger to jump through a flaming hoop, the tiger is first reinforced for jumping up on a certain pedestal, then for leaping from that pedestal to another.  Next the tiger has to jump through a hoop between the pedestals to get the reward.  Finally, the hoop is set afire, and the tiger must jump through it to get the reward.  This is an example of __________ .