When reviewing a tangible asset for possible impairment, which of the following statements is true?

An entity should recognize an impairment loss if the book value of the asset is more than the sum of the estimated future cash flows $($undiscounted$)$ from the asset.

An entity should recognize an impairment loss only if the asset is no longer being used in regular operations.

An entity should recognize an impairment loss if the historical purchase price of the asset is more than the asset$$s current purchase price.

An entity should recognize an impairment loss if the book value of the asset is more than the asset$$s fair value.