Agricultural economist: We can increase agricultural

Agricultural economist: We can increase agricultural production without reducing biodiversity, but only if we abandon conventional agriculture. Thus, if we choose to sustain economic growth, which requires increasing agricultural production, we should radically modify agricultural techniques.

Which one of the following principles, if valid, most helps to justify the agricultural economist's reasoning?

A) Agricultural production should be reduced if doing so would increase biodiveristy
B) Economic growth should not be pursued at the expense of a loss of biodiveristy
C) Economic growth should be sustained only as long as agricultural production continues to increase
D) Preserving biodiveristy is no more important than increasing agricultural production
E) Agricultural techniques should be radically modified only if doing so would further the extent to which we can increase agricultural production.


Are we looking to "strengthening" the author's conclusion? Or are we being asked to provide a premise that would better help us reach the conclusion? Is there a difference? I get confused when i see this type of question. Any help is greatly appreciated.