Islands, small nations, unstable nations, and impoverished countries are least likely to be affected by the brain drain phenomenon

Are you asking if this is true? because it's rather false!

they would actually be more likely to be affected by brain drain: the people who are looking for a good educiation would be less likely to find a job there and places mentioned would more likely experience brain drain as those people would leave for other places as they look for a better life!

Your answer is a distributive