A nursing professor wishes to determine if there is an association between her students grades and three independent variables (use of online tutorials, the use of quiz review sessions and participation in study sessions). Her regression model has a significant R square (0.83). She knows this means:

A). There is a clinically significant relationship between the use of resources and final grades.

B). She is unable to determine what the R square means without a p value.

C). She should include all the independent variables in her model because they are significant.

D. 83% of the variance in grades is explained by the independent variables included in the model.