A pig trained by the Brelands to pick up large wooden coins and deposit them in a wooden "piggy bank" learned quickly to do so for food rewards, but eventually a. reverted to rooting for the coins instead, in accordance with its natural approach to food. b. chose to wallow in the mud instead, in order to cool off. c. became too bored with the repetition of the task to continue. d. reverted to washing the coins instead, in accordance with its natural approach to food. ond to stimuli that are similar to an original conditioned stimulus is called a. generalization. b. habituation. c. aggregation. d. sensitization.