Question in Finance:

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What is the most preferred way of assigning values to D and E in calculating WACC for a firm? A. D-market value of all debt outstanding, E=market value of all equity outstanding B.D-book value of all debt outstanding, E-book value of all equity outstanding -D-market value of debt financing used by this project, E=market value of equity financing used by this project D.D=book value of debt financing used by this project, E-book value of equity financing used by this project