Answer:
d. Whenever events or changes in circumstances indicate that its carrying amount may not be recoverable.
Explanation:
It is advisable that an entity conducts impairment testing on an annual basis especially when the business is using International Financing Reporting Standards for preparing its financial statements.
However, under the US GAAP, impairment testing is only should only be undertaken when circumstances or events pointing to the fact the asset carrying value is not likely to be recovered, which is applicable in this case since we are dealing with US scenario where US GAAP applies
