[Solved] Hastorf and Johannessen argue that changes in the types of fuel used through time in the Upper Mantaro area of Peru are best explained by: A) changes in the abundance of high quality versus low quality fuel caused by environmental change. B) increasing population density that denuded the landscape of trees, forcing people to rely more and more on low quality fuel through time. C) forced fuel management programs mandated by an elite social class. D) a combination of materialistic and ideological explanations. Avoidance Learning: A type of learning in which a subject learns to avoid a stimulus or situation to prevent a negative outcome. Avoidance Training: A behavioral modification technique where a subject learns to avoid an unpleasant or undesirable outcome by performing a specific behavior. Skinner Box: An experimental apparatus used to study animal behavior, particularly the effects of reinforcement on learning, developed by B.F. Skinner. Buzzer Sounds: Audible alarms or signals produced by a buzzer, often used to indicate time limits, errors, or other notifications.