In accounting, what are the key principles governing the treatment of business combinations under Accounting Standards Codification $($ASC $805/$IFRS $3),$ and how are acquired assets and liabilities identified and valued during acquisitions?

A$)$ Recognition of acquired assets and liabilities at their fair values on the acquisition date

B$)$ Amortization of acquired intangible assets over their estimated useful lives

C$)$ Recognition of goodwill as the excess of the purchase price over the fair value of identifiable net assets acquired

D$)$ Presentation of acquired assets and liabilities at historical cost on the acquisition date