Q26

[mrudula_2005]

Why (B) and why not (E)? To me, all along, even whilst reading, I had thought to myself "this argument would be a lot stronger if the author showed that the insecticides typically used for mite control on strawberry plants actually kill the Typhlodromus predator mites" - and that's exactly what (B) says! how does that not strengthen the author's position? {it DIRECTLY strengthens lines 50-53, because the pesticide, in killing the predator, would indeed be doing far more harm than good}

and in terms of (E), it doesn't add any additional, independent support in my mind's eye. All it does is tell us something we alread know from the last paragraph of the passage where we see the results of field plantings of strawberries, where the predator populations reduced the outbreak of cyclamen mites and therefore could clearly have been able to tolerate the same range of climatic conditions that strawberry plants do (if E was not true, then the whole last paragraph could not have happened).

thoughts/help would be much appreciated, as always thank you!

[giladedelman]

Thanks for the question! I think you meant "Why (E), and not (B)?"

Be careful! About (B), you say that it would strengthen the author's position if it turned out that pesticides killed the predator mites. But the passage already says that! Look at lines 42-45:

"a second group was kept predator-free by
regular application of parathion, an insecticide that
kills the predatory species but does not affect the
cyclamen mite."

So the passage says that the pesticide kills only the predatory mites. What answer (B) would add is that the pesticide kills the non-predatory ones, too. But if that were true, it would actually weaken the author's position because it would suggest that pesticides are more effective than he admits.

Now, as for (E): the passage does not tell us that Typhlodromous can handle the same range of climates as strawberry plants! It just tells us about one experiment. Maybe those strawberry plants were in Texas; what about my aunt Helga's strawberry patch in Alaska? So (E) would definitely strengthen the author's position by suggesting that the use of this predator mite to protect strawberry plants could be widely applicable.

You dig?

[Elizabeth.Naff]

Can someone clear up what the question stem is asking?

Are the words "practical applicability" the key to the answer?
Is the question asking to strengthen to the author's claim about how predatory mites may be practically "used?"

Because then answer E makes more sense. If T tolerate the same conditions as strawberry plants then they are practically applicable to that habitat and, by extension, the habitat of cyclamen mites.

Or, is that not what is meant?

Thanks!

[Athomas87]

Is A wrong because it's irrelevent?

I originally picked it thinking that if they're laying more eggs, then they're better able to combat the prey.

[rinagoldfield]

Tough question/ passage! First, let’s clarify the argument:

Conclusion: “There is NO MORE effective means of reigning in pests than Natural Predators!” (line 1).

Why? Well, let’s look at the example of “T” predator and “CM” pests:

T helps take care of CM because it preys on it. Pesticides that knock out T lead to an outburst of CM.

(E) strengthens this argument by suggesting that T can be added everywhere necessary. In other words, it suggests that it is possible to use T in a widespread way. This strengthens the claim that natural predators are the MOST EFFECTIVE means to combating pests.

(A) is irrelevant. We care about T as a whole species, not individual mites.

(B) weakens. It suggests that pesticides may be able to curb the pests by killing off lots of different species, rather than simply targeting the helpful predators.

(C) is irrelevant. Weather doesn’t make a big impact here.

(D) is out of scope. We don’t care about other predators. Are T helpful or not?