GMAT Critical Reasoning (CR) | Re: The computer industry's estimate that it loses millions of

I found this question to be a bit tricky and I think the answer is B.
Going along the lines of argument if people who copy such programs are not interested in those programs, then probably they wouldn't purchase them even if purchasing was the only way

But I do not get why D is incorrect?

we are told that the market value of copied programs is low when compared to computer industry revenue.
Is this choice wrong because it doesn't tell us how much low is the market value of such programs?

suppose
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