sorry for the bad grammar

I don't think you fully understand the Development Commission's response to the Wildlife Commission. Like what jknauf said, its a strengthening question for the Development Commission's (DC) position against the Wildlife Commission's (WC) position. So we are looking for something that would strengthen the relationship between the DC's conclusion and premises. So there's a phrase in the argument that answer choice C would really strengthen when E is not really a part of his overall argument.

The DC's overall position starts off by stating that our nation is not like other industrialized nations that the WC is talking about; "we have not developed on wetlands in a flagrant manner at the expense of wild life". The DC even goes on to say that "We have conserved" to show that we are actually the opposite of those nations, to show that he is not against the WC's position; but rather, that the WC's position does not really apply in this situation. That is all context though, but the key phrase and premise (introduced by the since) from the DC's position that makes C is absolute right answer choice is this.

DC's position: "Since Figorian wetland development might not affect wildlife and is necessary for growth, we should allow development."

and answer choice c says...

Answer choice C: only when a reduction of endangered species by commercial development has been found should regulation be implemented to prevent further damage

That answer choices completely strengthens his argument! His premises for his conclusion to develop on wetlands depends on whether or not wetland development would affect wildlife. In answer choice C, he is saying that he would agree to regulation of wetland development only if there was proof or any evidence that the development of wetlands in their nation would harm such endangered species. You have to understand the his argument subtlety assumes that there has not been any evidence of such harm found in their nation. You also have to understand the his stance is that their nation is their nation is "much better"(might be exaggerating) than other nations at conservation efforts. To me, it even seems like the the DC might even be a little frustrated that his nation has to go through against the WC in order to use its own nation's resources, when other nations are just doing what they want to do with their respective resources (last sentence in his position). Thats why C is right because he concedes that his nation has implemented conservation efforts for endangered species, but if there is no proof (negation of the necessary condition in answer choice C) that wetland development would hurt any endangered species, or even wildlife in general, then there should be no regulations (literally the contrapositive of answer choice C).

Answer choice E says: It is imprudent to allow further depletion of natural resources

To me, answer choice E is just wrong. How has the nation of WC or DC been "imprudent" in its action? The DC even argues that they have been conserving despite the fact that other industrialized nations have been just plowing through their resources for growth. In fact, I think E is actually just the opposite of the DC's position. I think what you are trying to justify with E is what answer choice C does but a lot better because C does considers regulation, thus he does consider the possibility that the WC's position might be true. Personally, I think that the simplest way to rule out E is to see his argument as that we as a nation have been conservative enough, and we have considered the consequences of our action(which makes our action prudent), but unless you show me these so called consequences are a result of wetlands development, then we should be able to do whatever we want with these wetlands. This is probably a bad assumption and tone to put to the DC's position, but to me its the only possible way of saying why E is wrong without just saying that it would not make sense in his argument.

Hope that helps, I know I repeated myself a lot but that's just how I saw the DC's position. Good luck studying!

Thanks for the responses, and thank for the link Dillon, I had no clue about that new LSAC rule.