What's costing the US here is 'illiteracy' so any choice that deviates away from that is unclear.
It has been estimated that the annual cost to the United States of illiteracy in lost industrial output and tax revenues is at least $20 billion a year.
(A) the annual cost to the United States of illiteracy
in lost industrial output and tax revenues is at least $20 billion a year-this one suffers from a modification error...illiteracy IN LOST ...
-what the sentence should be saying is that the illiteracy costs the United States $20 billion a year IN LOST...
(B) the annual cost of illiteracy to the United States is at least $20 billion a year because of lost industrial output and tax revenues
-I don't see anything obviously wrong with this one, but it's not as direct and punchy as C
-perhaps the issue is 'because of...'
(C) illiteracy costs the United States at least $20 billion a year in lost industrial output and tax revenues
CORRECT(D) $20 billion a year in lost industrial output and tax revenues is the annual cost to the United States of illiteracy
-wordy
(E)
lost industrial output and tax revenues cost the United States at least $20 billion a year because of illiteracy
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