The new computer buyers are less profitable than "replacers". Last year higher profits then previous year, thus that means more "replacers" last year than previous year since that is how one can boost profits keeping the sales price and number of people who buy the computers same.
Hence pick D
I remember taking a sectional and getting it right but got it wrong when I was solving here. In the sectional I was pretty careful about getting this terminology clear in my head and making notes on scratch paper. While here, i thought I was super man

and tried to do it mentally not good. Test writers have tried to make it tricky by using "last year" and "previous year" terminology. here is the correct order per the question:
Current time > Last year > previous year
Cheers