Which of the Following Statements Is True

Which of the following statements is true?

A) A firm that uses a single cost of capital as a required rate of return for all its projects will lose out because it may reject profitable projects that have a risk level that is greater than
The average-risk project of the firm.
B) It is better for a firm to use a single cost of capital as a required rate of return for all projects because it will then maintain a constant risk level for the firm.
C) A firm that uses a single cost of capital as a required rate of return for all its projects may end up accepting unprofitable projects that have a risk level that is below average for the
Firm.
D) A firm that uses a single cost of capital as a required rate of return for all its projects may end up rejecting profitable projects that have a risk level that is below average for the firm.