The Reason Cash Flow Is Used in Capital Budgeting Is

The reason cash flow is used in capital budgeting is because

A) income rather than cash is used to purchase new machines.
B) cash outlays need not be evaluated in terms of the present value of the resultant cash inflows.
C) to ignore the tax shield provided from amortization ignores the cash flow provided by the machine which should be reinvested to replace old worn out machines.
D) all of the other answers are correct