The cash flows for four projects are shown below, along with the cost of capital for these projects. If these projects are mutually exclusive, which one should be taken? 0 1 2 3 4 - $20,000 $6000 $6000 $6000 $6000 4 0 1 2 3 $4000 $4000 $4000 $4000 A. Year: 5 Cash flow: OB. Year: 5 Cash flow: O C. Year: 5 Cash flow: O D. Year: 5 Cash flow: - $15,000 0 1 2 3 4 - $18,000 $5000 $5000 $5000 $5000 0 1 2 3 4 - $12,000 $4000 $4000 $4000 $4000