If Interaction Effects Make It Difficult for a Firm to Adjust

If interaction effects make it difficult for a firm to adjust its capital structure based on prevailing conditions, then

A) the firm should target a 50% debt/50% equity capital structure.
B) the firm should choose the capital structure that will minimize all transaction costs--both direct and indirect.
C) the firm should use as much debt financing as possible when it is financially healthy in order to benefit from lower corporate taxes.
D) the firm should use more equity financing than is necessarily optimal today in order to maintain financial flexibility.