In a world with no taxes, default risk or agency costs, Miller and Modigliani argue that your debt ratio is irrelevant and that your firm value will remain unchanged as the debt ratio changes. Assume now that you introduce tax benefits for debt and that you insure firms against default, what would you expect the right mix of debt and equity to be for a firm which is fully protected against bankruptcy? O Debt would still be irrelevant The firm should be all equity funded The firm should be all debt funded