Company QRS is looking to increase its leverage to take advantage of the tax shield, however, it is worried of the possible financial costs in the event of bankruptcy. Based on simulations of the firm's cash flows, QRS's financial analysts have made the following estimates (in millions) The firm has a beta of zero so that the appropriate discount rate for financial distress costs is the risk free rate of 4%. Determine the optimal debt choice for QRS, assuming financial distress costs will amount to 10 million. A. 40 million B. 50 million C. 60 million D. 70 million E. 80 million