The accumulation of what is subtracted from acquisition cost to determine net book value?

Net book value is calculated by taking the acquisition cost of an asset and subtracting accumulated depreciation. Accumulated depreciation represents the total amount of an asset’s cost that has been allocated as an expense over its useful life, reflecting the wear and tear or obsolescence of the asset.

This method allows businesses to account for the aging of an asset and provide a more accurate financial picture of its current value relative to its initial cost. By subtracting this accumulated amount from the original acquisition cost, the net book value gives stakeholders an updated view of what the asset is worth in financial terms at a particular point in time.

The other options do not relate to this calculation. Operating expenses are costs incurred during the normal running of a business and do not affect the computation of net book value directly. Market appreciation refers to any increase in an asset's market value, which is not considered in determining book value as it deals with accounting measures rather than market conditions. Amortization costs relate to the systematic write-off of intangible assets, not tangible assets, thus making them irrelevant in this context.