Explanation

Reading the question: we have to strengthen this argument, and as usual, the easiest way to strengthen will be first to weaken.

Creating a filter: Some companies have switched from genetically modified crops to non-modified. And, as a result, the argument goes, less genetically modified produce is being farmed than would otherwise be the cause. We can start with a basic relevance filter, and, hopefully, clean up with the negation test.

Applying the filter: What answer choices are connected to less genetically modified production? Choice (A) does not; it seems to focus on whether we are producing more unmodified than modified, but that's not the argument. Choice (B) concerns sale, not production, and has no implications for production, so (B) is out. Similarly, (C) concerns cost, not production, and is out. Similarly, (D) concerns farmland, not production, and is out. Choice (E) at least discusses production.

Logical proof: to confirm choice (E), we use the negation test. What if the new levels of unmodified produce required massive inputs of modified produce? For example, if unmodified produce was generated with modified seed or modified fertilizer? In that case, the argument would be damaged. The negated (E) critically damages the argument, so the un-negated (E) is a true strengthener. The correct answer is (E).