Please help with this question

Woodsburg's capital structure is 60% equity and 40% debt. Assuming all else constant, what will happen to Woodsburg's weighted average cost of capital (WACC) if its marginal tax rate increases? O A. It will decrease. OB. It will increase. OC. Depends on whether the tax rate is higher or lower than the 40% debt ratio. OD. It will remain same. OE. Depends on the relative magnitudes of the costs of debt and equity