- Industry has both an expertise in handling oil and an understanding of the cost entailed
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Industry alone should be responsible for devising safety standards
In addition, there is another argument that says...
- Double-hull creates new safety issues and would be burdensome to the industry and consumers
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Implementing a double-hull proposal isn't feasible
Now clearly the question is primarily concerned with the latter argument, probably because that argument mores goes against the environmentalist's claim that "govt. has to require oil companies to put double hulls on their tankers..."
However, could the question have asked us to strengthen either argument? If not, why not?
Just to help others out if any other questions exist, (B) (C) and (E) do not relate to the argument at all. Meanwhile, (A) weakens because it shows why the double-hull might be a good thing. (D) is the right answer because it explains more about the safety issues, perhaps showing why these issues make the double-hull not so feasible.