On January 1, five years ago, a business acquired an asset with a 35 year estimated useful life. On January 1 of this year, a review of estimated useful life determined that the estimated life should be 45 more years. as a result of the review, and in compliance with GAAP,

A- The original cost should be amortized over the next 45 years

B- the unamortized cost should be amortized over the next 40 years

C- the unamortized cost should be amortized over the next 30 years

D-the unamortized cost should be amortized over the next 45 years