1. Match the following terms with their correct definition. Definition options: A. Increases and decreases in the frequency of diseases over a period of years or within each year; B. The response of a group of people circumscribed in a place to a common etiologic factor to which they were exposed almost simultaneously; C. An unusual aggregation of health events grouped together in space or time; D. An outbreak that lasts longer than the time span of a single incubation period and is caused by a common source of exposure; E. An outbreak due to exposure of a group of persons to the same noxious influence..