perfectstranger wrote:
The argument is most vulnerable to the objection that it fails to
Alright. So it's a flaw question (notice that the stem doesn't have the "if true" language)
perfectstranger wrote:
Rye sown in the fall and plowed into the soil in early spring leaves a residue that is highly effective at controlling broad-leaved weeds, but unfortunately for only about forty-five days. No major agricultural crop matures from seed in as little as forty-five days. Synthetic herbicides, on the other hand, although not any longer-lasting, can be reapplied as the crop grows. Clearly, therefore, for major agricultural crops, plowing rye into the soil can play no part in effective weed control.
Alright so in their words:
1. Rye used in a particular way is highly effective at controlling certain types of weed but only for 45 days
2. No major agricultural crop matures in 45 days. (A lot of modifiers- no, major, agricultural! As
GMATNinja says, these modifiers should make your ears stand)
3. SH are longer lasting since they can be reapplied *as* crop grows. (Okay so this addresses a problem implicitly mentioned previously - Rye needs to be sown in fall and then plowed in early sprint - and so we cannot have any other crop growing at that time. On the other hand SH enables us to do so. Great!)
4. Conclusion: *for major agricultural crops* plowing Rye can play *no* part in *effective weed control*. (Woah! A bit more extreme conclusion. Just because something takes time, doesn't mean it's not effective but let us avoid getting into our words now)
perfectstranger wrote:
(A) consider that there might be minor, quick-growing crops that do mature in forty-five days or less
Sure it would be nice if they considered but this statement doesn't weaken the conclusion that Rye can play *no* part.
perfectstranger wrote:
(B) identify any alternative method of weed control that could be used instead of the method it rejects
Well, it did identify a method! This is out.
perfectstranger wrote:
(C) distinguish among the various kinds of synthetic herbicides
Distinguishing among various kinds of herbicides will not help shed more light on the effectiveness of Rye. This is out too.
perfectstranger wrote:
(D) allow for the possibility of combining the two weed-control methods it mentions
Hmm. This is very vague so need to give it some thought. The two methods it mentions are: Rye and SH. Now if they are combined to be something even more effective, then we cannot dismiss that Rye can play no part, right? Of course, it may be the case that things get worse when we combine it but, hey, before dismissing it altogether this argument didn't even consider all possibilities and this is taking a note. Let's keep it.
perfectstranger wrote:
(E) allow for the possibility that plants other than rye, handled the same way, might have the same effect.
Again, it would be nice if they told that but this is not a flaw in the way this argument reaches the conclusion.
D is your answer.