會計估計or原則的變動? - 會計

題目是:

At the time Marsh became a subsidiary of Ross, Marsh switched depreciation

of its plant assets from sum-of-the-years digits to straight-line that

was used by Ross.With respect to Marsh, this change was a:

A. change in an accounting estimate.

B. correction of an error.

C. change in accounting principle

答案:折舊方法的變動已視為會計估計變動(change in an accounting estimate),

原為會計原則變動----->Ans = A

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上面原題完整打上

不懂為何不是C @@
或者說我看不懂答案想表達甚麼@@

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