The Relationship Between Hours of Preparation and Average Score on a Field

The relationship between hours of preparation and average score on a field exam routinely administered Friday and Saturday evenings is captured in this plot. Which of these statements is best?

A) ^{A linear transformation would permit a good regression line fit.}
B) A squared transformation would permit a good regression fit.
C) A cubic transformation would permit a good regression fit.
D) An inverse transformation would permit a good regression fit