A Scatterplot, Residual Plot, and a Boxplot of Residuals from the Minitab

Multiple Choice

A scatterplot, residual plot, and a boxplot of residuals from the Minitab output are based on summary quantities given for x = Weight of a fully-grown green iguana (in kilograms) and y = Length of its tail (in centimeters) . Does it appear that the assumptions of the simple linear regression model are plausible? ​ ​

A) Yes, all the graphs show that a linear regression model is reasonable.
B) No, because the magnitude of residuals tends to decrease as the weight of species increases.
C) No, because the scatterplot shows that a curvilinear regression model is appropriate.
D) No, because the boxplot shows that vertical deviations are not normally distributed.
E) No, because some curvature is evident on the residual plot.