Serena says that if a regression line is drawn correctly in a scatterplot, there will always be the same number of points above the line as there are below the line. Which of these must be a counterexample to her claim?

With an odd number of points and none on the regression line, every point is either above or below it. The points would have to split into equal groups for Serena’s claim to hold, but two equal groups always contain an even total number of points. So choice A, an odd number of points with none on the line, must be a counterexample.

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