According to the research studies, the correlation between high intelligence and leadership is "<u>moderate; having a leader who is smarter, but not too smart, works best."</u>
This is because the research studies conducted revealed that leaders with a higher IQ to 120 have positive outcomes when it comes to leadership effectiveness.
However, from the IQ of 120 and above, the positive outcomes in leadership effectiveness regress gradually as the IQ of leaders increases from 120.
Hence, in this case, it is concluded that the correct answer is option C. "moderate; having a leader who is smarter, but not too smart, works best."
Learn more here: brainly.com/question/7639253