Which of the Following Should Not Be Reported Retroactively

Multiple Choice

Which of the following should not be reported retroactively?

A) Use of an unacceptable accounting principle, then changing to an acceptable accounting principle
B) Correction of an overstatement of ending inventory made two years ago
C) Use of an unrealistic accounting estimate, then changing to a realistic estimate
D) Change from a good faith but erroneous estimate to a new estimate