Task: Question Answering
Input (English): Which of the following is a correct statement about correlation?
(A)If the slope of the regression line is exactly 1, then the correlation is exactly 1. (B)If the correlation is 0, then the slope of the regression line is undefined. (C)Switching which variable is called x and which is called y changes the sign of the correlation. (D)The correlation r is equal to the slope of the regression line when z-scores for the y-variable are plotted against z-scores for the x-variable.
Output (English): D