Final answer:
The incorrect statement about residual plots is that if there is an obvious pattern, the model is probably reasonable. In contrast, an obvious pattern usually indicates a poor model fit, as residuals should appear random if the model is appropriate.
Step-by-step explanation:
The statement about residual plots that is not true is: a) If there is an obvious pattern, the model is probably reasonable. When analyzing residual plots, the presence of a pattern usually indicates that the model is not a good fit for the data. Residuals should appear random and have no discernible pattern if the model is appropriate. Therefore, a model is not probably reasonable if there is an obvious pattern in the residual plot. Other characteristics of a residual plot include: b) The x-axis appears in the middle of the graph, c) The vertical axis shows residuals, and d) The sum of the residuals is 0, which are all true statements.