The correct answer is "For different reasons, including: pathogens developed resistance, people traveling much more frequently and practices of terrorism".
Explanation:
Emerging diseases are infectious diseases that are new to a region, or that remerge from a place that were believed to be eradicated. For different reasons emerging diseases are appearing in industrialized countries. One is that pathogens may have developed resistance to the treatments, as they may evolved naturally or it was driven by overuse of antibiotics. Other is that people are traveling much more frequently than in the past, which helps pathogens from distance places to reach industrialized areas. Also, terrorism practices is a cause of introducing pathogens deliberately to a new place.
