Suppose That the Value of R² for an Estimated Regression

Multiple Choice

Suppose that the value of R² for an estimated regression model is exactly one. Which of the following are true?
(I) All of the data points must lie exactly on the line
(ii) All of the residuals must be zero
(iii) All of the variability of y about is mean have has been explained by the model
(I) The fitted line will be horizontal with respect to all of the explanatory variables

A) (ii) and (iv) only
B) (i) and (iii) only
C) (i) , (ii) , and (iii) only
(I) , (ii) , (iii) , and (iv)