Which of the following statement about payback period analysis is NOT correct?

a) Payback period is defined as the number of years necessary for cash flows to recover the original investment. b) Both conventional payback and discounted payback ignore all cash flows that occur after the payback period. c) The more the payback, the more liquid the project. d) The discounted payback solves the conventional payback's problem of not considering the project's cost of capital in the payback calculation.