20. (C)
Question type: Analyze Argument Structure
The author’s point is that environmentalists concerns over pumping carbon dioxide into the deep ocean are unfounded.
Answer choice (C) accurately reflects the author’s point, and is therefore correct.
(A) sounds reasonable, but is not a point specifically made by the author.
(B) is mentioned in the passage, but it is not the industrial engineer’s main point.
(D) is mentioned in the passage, but it is not the industrial engineer’s main point.
(E) is a very attractive answer, and it is very reasonable, but it infers too far beyond the author’s point. He says that the environmentalists’ concerns are unfounded, but stops short of recommending that we indeed pump carbon dioxide into the deep ocean.