Which of the following rules is CORRECT for capital budgeting analysis?

a$.$ The interest paid on funds borrowed to finance a project must be included in estimates of the project$$s cash flows.

b$.$ If a new product cannibalizes sales of some of the firm$$s other products, this fact should not be incorporated into the estimate of the relevant cash flows. However, if the new product is complementary to some of the firm$$s other products, this fact should be reflected in the analysis.

c$.$ A proposed project$$s estimated net income as determined by the firm$$s accountants, using generally accepted accounting principles $($GAAP$),$ is discounted at the WACC, and if the PV of this income stream exceeds the project$$s cost$,$ the project should be accepted.

d$.$ Sunk costs are not included in the annual cash flows, but they must be deducted from the PV of the project$$s other costs when reaching the accept$/$reject decision.

e$.$ Only incremental cash flows, which are the cash flows that would result if a project is accepted, are relevant when making accept$/$reject decisions.