Choose the One Alternative That Best Completes the Statement or Answers

Choose the one alternative that best completes the statement or answers the question.
-Each year a nationally recognized publication conducts its "Survey of America's Best Graduate and Professional Schools." An academic advisor wants to predict the typical starting salary of a graduate at a top business school using GMAT score of the school as a predictor variable. A simple linear regression of SALARY versus GMAT using 25 data points shown below.
$$\mathrm { b } _ { 0 } = - 92040 \mathrm {~b} _ { 1 } = 228 \mathrm {~s} = 3213 \mathrm { R } ^ { 2 } = 0.66 \mathrm { r } = 0.81 \mathrm { df } = 23 \mathrm { t } = 6.67$$
Give a practical interpretation of $\mathrm { R } ^ { 2 } = 0.66$ .

A) $66 \%$ of the sample variation in SALARY can be explained by using GMAT in a straight-line model.
B) $66 \%$ of the differences in SALARY are caused by differences in GMAT scores.
C) We estimate SALARY to increase $\$ .66$ for every 1 -point increase in GMAT.
D) We can predict SALARY correctly $66 \%$ of the time using GMAT in a straight-line model.