My best answer would be C I hoped I helped sry if you get it wrong
Primary succession is when, for example, a volcano explodes and there is nothing left and even the soil is ruined. It would take at least a hundred years for the land to be like it was before the volcano erupted. Secondary succession is when, for example, a wild fire happens but the soil is not ruined. It would take at least 25-50 years for the land to be like it was before the fire.
A scientific theory is an explanation of an aspect of the natural world that can be repeatedly tested and verified in accordance with the scientific method, using accepted protocols of observation, measurement, and evaluation of results. Where possible, theories are tested under controlled conditions in an experiment.
