$4.$ Assume a Real Estate financing project has normal cash flows $($that is$,$ the initial cash flow is negative, and all other cash flows are positive$).$ Which of the following statements is most correct?

a$.$ All else equal, a project$$s IRR increases as the cost of capital declines.

b$.$ All else equal, a project$$s NPV increases as the cost of capital increases.

c$.$ All else equal, a project$$s MIRR is unaffected by changes in the cost of capital.

d$.$ Statements a and b are correct.

e$.$ None of above.