Problem: Researchers wanted to examine the relationship between smoking and chronic disease among older adults and the elderly in lower socio-economic areas. The researchers have identified those who have a chronic disease and those who do not have a chronic disease using existing medical records in order to make comparisons. Further, the researchers will ask participants about their behaviours, including smoking, prior to their diagnosis. Which of the following best describes the above: A. Prospective study B. Prospective cohort study C. Experimental D. Causal study E. None of the above are correct