The set of bivariate observation $\left(\mathrm{x}_1, \mathrm{y}_1\right),\left(\mathrm{x}_2, \mathrm{y}_2\right), \ldots . .\left(\mathrm{x}_{\mathrm{n}}, \mathrm{y}_{\mathrm{n}}\right)$ 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
• Correct answer
  D

  -1 and 1 only

Hence, the correct answer is option: 'D'.