If a firm uses the weighted average cost of capital (WACC) to discount cash flows of higher than average risk projects, which one of the following will most likely occur（）

A. Project NPVs will be understated.

B. The overall risk of the firm’ s investments will rise over time.

C. The WACC of the firm should fall over time.

如果圆的周长等于正方形的周长，那么圆的面积[ ]

A．大于正方形的面积

B．等于正方形的面积

C．小于正方形的面积