Both primary and secondary succession begin with pioneer species that... O a use up all the existing resources and prevent establishment of non-native organisms O b modify the area and allow larger...

Both primary and secondary succession begin with pioneer species that... O a use up all the existing resources and prevent establishment of non-native organisms O b modify the area and allow larger and more complex organisms to appear Oc change the area and make it safer from predatory organisms. O d invade the area so that new organisms cannot be established