21.Global warming is predicted to have an effect on all of the following except: A. rainfall patterns B. human reproduction C. agriculture D. sea levels 22.Which of the following is the single most important cause of extinction? A. Loss of the ozone layer B. Species overexploitation C. Habitat loss D. Nuclear accidents E. Introduced species 23.In which way can natural habitats be adversely affected by human influences? A. Pollution B. Destruction C. Habitat fragmentation D. Human disruption E. All of the choices are correct. Â Â