What was the main reason why australias economy collapsed right before the great depression began?

Which one of the following statements is true? ddt does not prevent disease from passing from agricultural animals to humans. cost was a major factor in the united states government's decision to ban ddt. many african governments concluded that the potential long-term health effects of ddt were not as serious as the immediate problem of insect control. ddt cannot accumulate in the fat of animals. the ddt ban in the united states has made it very difficult to control agricultural insect pests.