The author states that the process of eliminating the destructive by-products of the so-called
“clean coal” produces emissions.
The fragment of the text in which the underlined pronoun refers to the statement above is:
(A) it has to consist largely of euphemism. (£. 31)
(B) “clean coal” is one of these. (£. 33)
(C) ordinary coal which has been treated to “eliminate” most of its destructive by-products, (¢. 35]
(D) This, though, isn’t clear [¢. 36]