Depreciation represents a decrease in:

Market value of fixed assets
Market value of floating assets
Market value of debentures issued
Book value of fixed assets

The correct answer is: D. Book value of fixed assets.

Depreciation is the decrease in the value of an asset over time due to wear and tear, obsolescence, or other factors. It is a non-cash expense that is recorded on the income statement to reflect the decline in the value of the asset. The book value of an asset is its original cost minus accumulated depreciation.

Option A is incorrect because the market value of fixed assets is the price at which an asset could be sold in the open market. Depreciation does not affect the market value of an asset.

Option B is incorrect because the market value of floating assets is the price at which a short-term asset could be sold in the open market. Depreciation does not affect the market value of a floating asset.

Option C is incorrect because the market value of debentures issued is the price at which a debenture could be sold in the open market. Depreciation does not affect the market value of a debenture.

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