It is commonly believed that the extensive use of high-tech agricultural machinery is essential for maintaining soil health on large farms. However, evidence suggests that simply adopting no-till farming, which minimizes the disturbance of soil, is sufficient. This conclusion is supported by studies indicating that farms using no-till practices consistently report better soil health.
Which of the following, if true, most seriously weakens the force of the evidence cited?
(A) Many agricultural scientists continue to recommend traditional plowing techniques alongside modern machinery to prevent soil compaction and maintain fertility.
(B) Farms that combine no-till practices with traditional tilling methods report the highest levels of soil fertility and overall health.
(C) Farms using no-till farming often require high-tech agricultural machinery to effectively manage crop residue, which is not removed by tilling.
(D) The studies assessing soil health on farms using no-till practices were funded by manufacturers promoting high-tech farming equipment, potentially biasing the results.
(E) The metrics used to assess soil health in the studies are typically those that favor soils which have been recently tilled and chemically treated.
Deconstructing the argument:
Claim: Use of high tech machinery improves soil health.
Argument's counter-point: No-till farming is sufficient for soil health.
ˆThis also becomes the conclusion of the argument.
Evidence for the conclusion: farmers who use no till farming have better soil health.
The argument assumes that "better soil health" is achieved just by "no-till farming practice". To weaken this, we need to find something that shows there might be another factor improving soil health.
(A) Many agricultural scientists continue to recommend traditional plowing techniques alongside modern machinery to prevent soil compaction and maintain fertility.
Seems irrelevant; doesn't address the impact of no-till farming on soil health
(B) Farms that combine no-till practices with traditional tilling methods report the highest levels of soil fertility and overall health.
Ok, true. This is what the argument used as evidence but we still don;t know why they have good soil health.
(C) Farms using no-till farming often require high-tech agricultural machinery to effectively manage crop residue, which is not removed by tilling.
Ok, so here it says that farmers using no-till farming actually use high-tech machinery. So, perhaps, high tech machinery contributes to improving the soil health. If that were the case, then just practicing no-till farming isn't enough to ensure good soil health.
Therefore, this weakens the inference drawn from the evidence, that is, "farmers who practice no-till farming have better soil health due to no-till farming".
(D) The studies assessing soil health on farms using no-till practices were funded by manufacturers promoting high-tech farming equipment, potentially biasing the results.
If this were true, the results should be biased in favour of high-tech machinery, not otherwise.
(E) The metrics used to assess soil health in the studies are typically those that favor soils which have been recently tilled and chemically treated.
Again, if this were true, soil which were "tilled" would be in better health condition than otherwise
Hence, C is the correct answer.