Which one of the following is correct concerning the rules related to project analysis?
a. The average accounting return considers both the book value and the discount rate of a project.
b. You should accept a project only if the profitability index is less than 1.0.
c. The internal rate of return can lead to faulty decisions if two mutually exclusive projects are of different sizes.
d. The net present value method is only applicable if a project has conventional cash flows.
e. The payback method is best used for research and development projects.