An investment project has annual cash inflows of $4,500, $5,600, $6,400, and $7,700, and a discount rate of 12 percent. Required: What is the discounted payback period for these cash flows if the initial cost is $7,500? (Do not round your intermediate calculations.)

A: 0.78 years

B:1.78 years

C:2.53 years

D: 1.28 years

E:3.56 years