The set of bivariate observation (x1, y1), (x2, y2), .....(xn, yn) are such that all the values are distinct and all the observations fall on a straight line with non-zero slope. Then the possible values of the correlation coefficient between x and y are
a. 0 and 1 only
b. 0 and –1 only
c. 0, 1 and –1
d. –1 and 1 only
