Which of the following statements is true? The payback investment rule is based on the notion that an opportunity that pays back its initial investments quickly is not a good idea O An internal rate of return (IRR) can't be a negative number for an investment opportunity. O Net present value (NPV) always is less reliable than IRR for an investment opportunity. O In general, there can be as many internal rates of return (IRRs) as the number of times the project's cash flows change sign over time