Myers Company Acquired Machinery on January 1, 2010 Which It

Myers Company acquired machinery on January 1, 2010 which it depreciated under the straight-line method with an estimated life of fifteen years and no residual value.On January 1, 2015, Myers estimated that the remaining life of this machinery was six years with no residual value.How should this change be accounted for by Myers?

A) As a prior period adjustment
B) As the cumulative effect of a change in accounting principle in 2015
C) By setting future annual depreciation equal to one-sixth of the book value on January 1, 2015
D) By continuing to depreciate the machinery over the original fifteen year life