The statement that is fair, focused, and complex is:
"A research psychologist recently published a case study showing that natural talent combined with consistent effort produces measurably higher success rates."
This statement is fair because it presents a balanced view of the relationship between natural talent and hard work, rather than dismissing one in favor of the other. It is focused because it clearly states the connection being investigated (natural talent, effort, and success). Finally, it is complex because it acknowledges that both natural talent and effort can interplay to influence success rather than attributing success solely to one factor.