Jobart Company is currently operating at full capacity. It is considering buying a part from an outside supplier rather than making it in-house. If Jobart purchases the part, it can use the released productive capacity to generate additional income of $30,000 from producing a different product. When conducting incremental analysis in this make-or-buy decision, the company should:
(a) ignore the $30,000.
(b) add $30,000 to other costs in the "Make" column.
(c) add $30,000 to other costs in the "Buy" column.
(d) subtract $30,000 from the other costs in the "Make" column.