Consistency is implicit in audit report.i.e. if the same set of GAAP are used prior years and current year, auditor does not have to mention this in his report(everythign o.k). But when accounting principle is changed from one acceptable GAAP to another acceptable GAAP(choice A) and the client is justified as to change(i.e. to present F.S more fairly), the auditor needs to modify his report for consistency. Choice B is not change in accounting principle, but is change in accounting estimate, therefor no consistency modification is required.  

hope this will work......................

Is answer B correct? Becker passmaster does say that the correct answer is B. However Becker text book clearly says that quote" although a change in depreciation method is accounted for as a change in estimate for financial purposes, for purposes of auditor's report, changes in depreciation method do require the addition of an explanatory paragraph."

Am I missing something here?

Answer B is not a change in method.  A change in method would be from sum of years to straight line.   It is a change in estimate.  An example is 10 year useful life to 8 years.