The information gained from environmental epidemiologic studies can be very helpful in trying to ...

The information gained from environmental epidemiologic studies can be very helpful in trying to identify whether an exposure or what particular exposures have made people ill. Major challenges to most environmental epidemiology studies include:
 
  (Select all that apply).
  A) Resource intensive in terms of personnel and money
  B) Period between exposure and illness can be very short
  C) Weak ability to identify outbreaks of infectious disease
  D) Limited availability of data on many contaminants and their effect on people's health
  E) Time consuming to perform