7.The rising cost and frequency of natural disasters can be blamed only partly on the weather. Disasters are also on the rise because more people are located in harm’s way. In states like Texas, Arizona, and California the buildup of neighborhoods in former woodlands has exposed more properties to wildfires, just as costal development in states like Florida, North Carolina, and Maryland has exposed expensive beach houses and hotels to hurricanes and other storms.____ , the rapid growth of megacities in developing countries in Asia and Africa has made millions more vulnerable to heat waves and floods.,(A)so (B) however (C) on the other hand (D)at the same time