A set of data has correlation coefficient r. For which value of r would the average magnitude of theresiduals be the smallest?

The correlation coefficient, denoted by r, is a measure of the strength of the straight-line or linear relationship between two variables. The correlation coefficient takes on values ranging between +1 and -1. 0 indicates no linear relationship.
So, from the options:
[tex]-0.034\to0[/tex]is the best choice