For most companies, the effective tax rate is lower than the marginal tax rate. For such companies, using the effective tax rate (instead of the marginal tax rate) in perpetuity to compute the after tax operating income will result in which of the following?

A) It depends on the level of debt, or the D/E ratio

B) It should have no effect on the value of the company

C)We will understate the value of the company

D We will overstate the value of the company