Answer:
(b) two months later, ask the same group of people to report how many times they have gambled recently
Explanation:
In research and statistics, criterion validity is also referred to as criterion-related validity and is described as validity that measures or analyzes how well a specific measure tends to predict the outcome of some other measure. If a specified test requires to measure or predict behavior or performance in some other situation utilizes the criterion validity. In criterion validity, a particular measure is directly related to its outcome.
The correct answer for the given question is b.