If the correlation coefficient r = 1.00,then all the observations must fall exactly on:

A) a straight line with a slope that equals 1.00.
B) a straight line with a negative slope.
C) a straight line with a positive slope.
D) a horizontal straight line with a zero slope.

A correlation coefficient of 1.00 indicates a perfect positive correlation, which means that all the observations on a scatter plot will fall perfectly on a straight line with a positive slope. A correlation coefficient of -1.00 would indicate a perfect negative correlation and a straight line with a negative slope. A correlation coefficient of 0 would indicate no correlation and the observations would be scattered randomly. A slope of 1.00 or 0 does not necessarily indicate a perfect correlation.