Choice "D" is correct. A project's net present value is a function of current and future cash flows, including proceeds from the sale of the old asset.
Choice "a" is incorrect. A project's net present value is a function of current and future cash flows. The carrying amount of the asset does not affect cash flows.
Choice "c" is incorrect. A project's net present value is a function of current and future cash flows. Depreciation is a noncash item and does not affect cash flows.
Choice "b" is incorrect. A project's net present value is a function of current and future cash flows. Depreciation is a noncash item and does not affect cash flows.