Deep tillage is even more deleterious to the world's topsoil supply

Question

Deep tillage is even more deleterious to the world's topsoil supply than previously believed. For example, farmers who till deeply are ten times more likely to lose topsoil to erosion than are farmers who use no-till methods. Results like these make it clear that farmers who now till deeply should strive, by using other topsoil aeration techniques, to incorporate no-till methods instead.

The argument depends on assuming which one of the following?

(A) Topsoil erosion does not make farmers want to till more deeply.

(B) In deep-tillage farming, the deeper one tills, the greater the susceptibility to topsoil erosion.

(C) Tilling by any method other than deep tillage is not a viable option.

(D) The most expensive farming methods employ topsoil aeration techniques other than deep tillage.

(E) On average, topsoil that is no-tilled is more aerated than topsoil that is tilled deeply.

MartyMurray · Answer

Deep tillage is even more deleterious to the world's topsoil supply than previously believed. For example, farmers who till deeply are ten times more likely to lose topsoil to erosion than are farmers who use no-till methods. Results like these make it clear that farmers who now till deeply should strive, by using other topsoil aeration techniques, to incorporate no-till methods instead.

The main conclusion of the argument is the following:

farmers who now till deeply should strive, by using other topsoil aeration techniques, to incorporate no-till methods instead

The main conclusion is supported by the following intermediate conclusion:

Deep tillage is even more deleterious to the world's topsoil supply than previously believed.

which is suppported by the following example:

For example, farmers who till deeply are ten times more likely to lose topsoil to erosion than are farmers who use no-till methods.

We see that the author of the argument has observed a correlation between deep tillage and increased topsoli erosion, "farmers who till deeply are ten times more likely to lose topsoil," and concluded, essentially, that deep tillage causes increased topsoil erosion and therefore should be replaced with no-till methods.

The argument depends on assuming which one of the following?

This is an Assumption question, and the correct answer will state an assumption necessary for the premise to support the conclusion.

(A) Topsoil erosion does not make farmers want to till more deeply.

This choice is a little hard to eliminate because it could seem to present an alternative cause-effect relationship. We might think that the relationship may not be that deep tillage causes erosion but that erosion causes farmers to want to use deep tillage.

Notice, however, that this choice does not say that erosion does not cause farmers to use deep tillage rather than another method. It says that it doesn't cause them to  want  to till "more deeply." So, maybe they are already using deep tillage when the erosion begins.

Honestly, in a GMAT question, this choice might be correct. However, in an LSAT question, little differences such as "deep tillage" versus "till more deeply can make a choice incorrect.

Eliminate.

(B) In deep-tillage farming, the deeper one tills, the greater the susceptibility to topsoil erosion.

The argument does not involve any claims about the effects of tillling deeper.

Also, regardless of whether this choice is true, it remains the case that more soil erosion occurred when deep tilling was done, and that evidence supports the conclusion.

So, this argument doesn't depend on this choice.

Eliminate.

(C) Tilling by any method other than deep tillage is not a viable option.

This choice is interesting.

The argument goes from the fact that deep tillage is associated with greater topsoil erosion to the conclusion that "farmers who now till deeply should strive, by using other topsoil aeration techniques, to incorporate no-till methods instead."

Notice that, in working that way, the argument relies on the assumption that there is no other option. After all, if there is another option, then it doesn't make sense to conclude that farmers should jump to using no-till methods instead. Rather, they could switch to using another method of tilling.

So, the argument relies on it being true that there's not another viable tilling method.

Keep.

(D) The most expensive farming methods employ topsoil aeration techniques other than deep tillage.

If anything, this choice is a reason to use deep tillage to minimize expense.

Since the author is arguing for ceasing to use deep tillage, if anything, this choice goes against the argument.

Eliminate.

(E) On average, topsoil that is no-tilled is more aerated than topsoil that is tilled deeply.

The conclusion of the argument is not about using no-till methods to achieve more aeration. It's about using no-till methods to prevent erosion.

So, regardless of whether this choice is true, the argument works.

Eliminate.

Correct answer:  C

Akkiiii · Answer

Should the answer not be E since it makes more sense when we have assumed that " farmers who till deeply are ten times more likely to lose topsoil to erosion than are farmers who use no-till methods" then  we can conclude how  "topsoil that is no-tilled is more aerated than topsoil that is tilled deeply."

Can anybody please help in explaining how C is the right option?
Thanks

Oppenheimer1945 · Answer

I also marked A, why OA given is C?

PRAGATIOSTWAL · Answer

Can someone please explain how assuming Option C makes sense here?

MartyMurray · Answer

I changed my explanation. See what it says for (C) now.

You have to be so careful answering LSAT questions. They often work differently from GMAT questions.

In this case, (A) might be correct if this were a GMAT question, but in a LSAT question, the slight difference between "deep tillage" and "more deeply" is enough to make (A) incorrect, with the result that (C), in which the meaning of "viable" is not 100 percent clear and which is thus barely correct, is the best answer.

ashutosh_73 · Answer

Hi  MartyMurray  ,

I think, even if (A) says: ''Topsoil erosion does not make farmers want to  use Deep tillage'' ,(A) may not be the correct answer.
Because argument says:   ''Deep tillage is even more deleterious to the world's topsoil supply than previously believed.''

So, farmers or no farmers, above premise still stands true. Maybe, it has been proved experimentally.
Even if Farmers '' want '' to use '' Deep tillage '', they will still be better off to use other techniques, as the argument has suggested.
Also, what Farmers '' Want '' and '' what actually do''  are two diffirent things.

Guntabulla · Answer

The main conclusion of the paragraph is that farmers should use no-till instead of deep tilling. 
However a third option does exist which is light/moderate tilling. But since the paragraph doesn't even consider that option and sees the options as black or white, the author clearly is assuming that light tilling is not viable.
If it was there would have been a consideration for such an option.

Hence C is the logical answer here

MartyMurray · Answer

I agree with a lot of what you said, but that statement is not a premise. It's a conclusion of the author's.

Elite097 · Answer

KarishmaB  Im really not following the argument . Pls can you explain this in detail along with A and C and the play of terminologies

Posted from my mobile device

HarishD · Answer

Deep tillage is even more deleterious to the world's topsoil supply than previously believed. For example, farmers who till deeply are ten times more likely to lose topsoil to erosion than are farmers who use no-till methods.  Results like these make it clear that farmers who now till deeply should strive, by using other topsoil aeration techniques, to incorporate no-till methods instead.

My understanding from the last line:  
"Famers DONOT want to STOP deep-till and incorporate no-till method, INSTEAD they come up with topsoil aeration technique TO AVOID EROSION"

Pre Thinking: As they do not want to stop using deep-till, that must be the most efficient way for the crops, even though it cause soil erosion (that can be avoided by using topsoil aeration techniques).
Something GOOD with deep-till technique.

I was looking for option which says good about deep-till.

Option C) Tilling by any method other than deep tillage is not a viable option.
  Bang -On

You can look for other posts, if you want to know why other options are wrong. I got my answer my using this approach.

VerbalBot · Answer

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Deep tillage is even more deleterious to the world's topsoil supply

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Deep tillage is even more deleterious to the world's topsoil supply

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