Even If a Residual May Be Unusually Large, the Standardized

Even if a residual may be unusually large, the standardized residual rule might not identify the observation as being an outlier. How can this difficulty be circumvented?

A) by using studentized deleted residuals
B) by performing a logistic regression
C) through linear discriminate analysis
D) It cannot be circumvented and should be considered a component of the validation process.