is twice as much as that which is being emitted annually by allmotor vehicles in the Chicago Metro area
Being emitted is WORDY
B. as much annually as is emitted by the
We need 'all' before 'motor vehicles'
C. as much compared to what is annually emitted by all
'as much' anticipates the use of 'as'
D. that emitted annually by all
THAT emitted by ALL -correct
E. that emitted annually compared to
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