Depreciation is a) the sum of gross and net investment. b) new additions to a firm's stock of intangible capital. c) the decline in the economic value of an asset over time. d) the decrease in the general price level.

The correct answer is C. the decline in the economic value of an asset over time

Explanation:

Depreciation : Depreciation is a decreasing value of the asset due to tear and wear, obsolesce, usage, etc

It is charged on the fixed assets which include plant and machinery, furniture and fixtures, building, computer, equipment, etc.

The sum of gross and net investment is not called the depreciation because gross investment is an expenditure which is incurred on new purchase while net investment is a difference between gross investment and deprecation. So, option B is incorrect.

Depreciation should not be charged on intangible assets because in intangible asset, the amortization is charged. Thus, option B is incorrect.

The decrease in the general price level is disinflation or inflation decreased. So, option D is also wrong

Hence, The correct answer is C. the decline in the economic value of an asset over time

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