Final answer:
People are best at using base rate knowledge when they have access to both base rate and diagnostic info, as it allows for more informed and accurate judgments.
Step-by-step explanation:
In which scenario are people good at using base rate knowledge? The correct answer is (c) given base rate and diagnostic info. People generally make more accurate judgments when they have access to both categories of information. Base rate information provides the context or how often an event generally occurs, while diagnostic info offers more specific, pertinent data related to the particular situation.
For example, knowing that a particular disease has a prevalence (base rate information) of 1% in the population provides a general likelihood of someone having the disease, but combined with diagnostic information such as symptoms and test results, a medical professional can make a much more accurate diagnosis.