Why is cut often more impactful on a diamond's brilliance than carat alone, and how does this relate to grading?

Why is cut often more impactful on a diamond's brilliance than carat alone, and how does this relate to grading?

• A. Because color is more important; cut does not affect light; grading uses only carat, color.
• B. Because fluorescence is the main factor; cut is irrelevant; grading focuses on color.
• C. Because cut governs light performance; even a smaller stone with a superb cut can outperform a larger stone with a poor cut, and labs grade cut as Excellent or Very Good.
• D. Because carat weight is the only determinant; cut has no effect; grading does not include cut.

Answer: (C)