Answer:
B. They take less time
Explanation:
Cohort studies are usually more time consuming and requires a high amount of resources. The reason behind this is that the cohort research is a form of a longitudinal study which means that the research focuses on a cohort over a period of time. For instance, the time period is six months then the research will take at least eight to nine months because of the six month gap between the two data collection phases. Hence, it is very time consuming and this is certainly not considered a benefit of cohort studies.
