Byrd Company Experienced an Accounting Event That Affected the Elements

Byrd Company experienced an accounting event that affected the elements of its financial statements as indicated below:

Which of the following accounting events could have caused these effects?

A) Recognized depletion expense under the units-of-production method.
B) Recognized depreciation expense under the double-declining-balance method.
C) Amortized patent cost under the straight-line method.
D) All of these answer choices are correct.