Well it surely isn't nuclear, or electrical. It's not radiant either.. So the only answer is chemical.
Based on my observations, I can conclude that lithospheric motion of the South American plate with the Nazca plate and the African plate causes the earthquakes to engage nearest to volcanic activity causing it to either erupt the volcano, or increase the damage caused by the volcano.
The big idea to remember is that mitosis is the simple duplication of a cell and all of its parts. It duplicates its DNA and the two new cells (daughter cells) have the same pieces and genetic code. Two identical copies come from one original. Start with one; get two that are the same. You get the idea.
So it is the very last stage!