The author of the passage mentions the number of ice ages in the third paragraph most probably in order to A. provide proof that cooler and drier temperatures are primarily responsible for the distribution of species in the Amazon B. explain how populations of species were protected from extinction in the Amazon basin C. explain how most existing species were able to survive periodic climatic disturbances in the Amazon basin D. suggest that certain kinds of climatic disturbances cause more species diversity than do other kinds of climatic disturbances E. suggest that geographic isolation may have occurred often enough to cause high species diversity in the Amazon basin