Please explain in as much detail as possible, I'm trying to study for the final and want to understand these questions. Thank you so much

8. Which one of the following statements is correct? Assume cash flows are conventional. A) When the internal rate of return is greater than the required return, the net present value is positive. B) Projects with conventional cash flows have multiple internal rates of return. C) If two projects are mutually exclusive, you should select the project with the longest payback period. D) The profitability index will be greater than 1.0 when the net present value is negative. E) The average accounting return is unaffected by how the asset is depreciated