The Colorado beetle originally fed on a particular type of plant. Howe

Question

The Colorado beetle originally fed on a particular type of plant. However, after the potato was introduced into the beetle’s habitat, female Colorado beetles began laying their eggs on the underside of the leaves of the potato plant. After about two weeks, the eggs hatch and the larvae begin feeding on the leaves, oftentimes devastating the potato crop. Most efforts to control the Colorado beetle are directed at using pesticides to kill the larvae.

Which of the following, if true, most strongly supports the view that controlling the Colorado beetle by using pesticides to kill its larvae is NOT advisable?
A. Colorado beetles have many natural predators.
B. Once mature, the Colorado beetle is no longer a threat to the potato crop.
C. Because the Colorado beetle reproduces so rapidly, it quickly develops a resistance to toxins.
D. Farmers would have to apply the pesticides numerous times during the growing season.
E. Some of the Colorado beetle larvae will not be destroyed by the pesticide.

Source: McGraw-Hill's GMAT

abhimahna · Answer

The argument is saying Colorado beetle is devastating the potato crop. So, we can kill them by pesticide.

Weakener: This pesticide could be harmful for the crop. Or beetles in some time become resistant to this pesticide.

A. Colorado beetles have many natural predators.  : So, No relation with our argument. Incorrect 
B. Once mature, the Colorado beetle is no longer a threat to the potato crop.  : Once mature?? Wow, it would have already done the damage to us. Incorrect. 
C. Because the Colorado beetle reproduces so rapidly, it quickly develops a resistance to toxins. :  Nice, Keep it aside for a moment. 
D. Farmers would have to apply the pesticides numerous times during the growing season.  So, They can do so. Right? No relation. Incorrect. 
E. Some of the Colorado beetle larvae will not be destroyed by the pesticide.  : Some won't be destroyed. Fine. rest will be. Hence, atleast we can save something. Incorrect.

Only option left is C. Hence, correct.

mvictor · Answer

i'll go with D as well.
since the beetle will develop resistance to pests, it will no longer be effective, and therefore, illogical to use pests.

abhimahna · Answer

Hey buddy, I think you meant C as D cannot be the correct answer.

aragonn · Answer

This is a weakener. so lets find the conclusion, which is --- Most efforts to control the Colorado beetle are directed at using pesticides to kill the larvae. ---- and weaken it.

I have eliminated A, B and D easily, but got stuck b/w C & E.

C - if this is true the in long terms pesticides will be useless and need to make adjustments to it. but yes in the end we can control them through this method. for the immediate effects, it should be effective, cause resistance develops in time, here quickly can't be 1-2 days. there are pros and cons with this choice.

E - So every time we destroy the larvae, they will not be completely destroyed and in the end it will cause some loss in immediate + probably re-population of bugs.--- if this true then it can cause serious effects.

both choices are quiet close. Please some help.

aragonn · Answer

This is a weakener. so lets find the conclusion, which is --- Most efforts to control the Colorado beetle are directed at using pesticides to kill the larvae. ---- and weaken it.

I have eliminated A, B and D easily, but got stuck b/w C & E.

C - if this is true the in long terms pesticides will be useless and need to make adjustments to it. but yes in the end we can control them through this method. for the immediate effects, it should be effective, cause resistence develops in time, here quickly can't be 1-2 days. there are pros and cons with this choice.

E - So every time we destro the larvae, they will not be completly destroyed and in the end it will cause some loss in immediate + probably repopulation of bugs.--- if this true then it can cause serious effects.

both choices are quiet close.

RMD007 · Answer

Expert, please advise how C is the right answer here. From the general knowledge it can be understood that Pesticides may contain some toxins and if beetels develops resistance to toxins the conclusion is likely to fail.

But such a premise (that Pesticides may contain some toxins) is not explicitly stated in the argument.

But such a premise (that Pesticides may contain some toxins) is not explicitly stated in the argument.

broall · Answer

Toxins (to beetels) here means pesticides.

jkolachi · Answer

C seems like the best option. If resistance is developed, then using pesticide will be pointless. E is a close second but C is a much better option. Rest seems irrelevant.

Cheers.

SUV0508 · Answer

In the argument, the problem is that the larvae eat the potato leaves and hence destroy the crops. But option C is treating the beetles as the source of problem. Also what does rapid reproduction have to do with the beetles developing a quick resistance to toxins?

ReedArnoldMPREP · Answer

The larvae come from beetle reproduction. They are the 'baby beetles.'

We don't really need to understand *why* rapid reproduction helps the beetles develop a quick resistance to toxins. C could be "Because  , it quickly develops a resistance to toxins." The fact that there's *anything* that causes the beetle to quickly become resistance to toxins makes the use of pesticide (a toxin) a less than ideal strategy, as the beetle could very well become resistant to it quickly.

Think of this situation:

"John bakes delicious cookies. When he brings them to the office, everyone is happy. He usually brings them the first Tuesday of every month, which next Tuesday. But if he brings freshly baked cookies next Tuesday, they probably will not make the office happy, because __________"

C). Since John's break-up with his partner, he has been unfocused and his baking has suffered.

So the argument is about the cookies (the larva) that usually make the office happy (that devastate the potato crops), but the cookies come from John (the larvae are born from the beetles.) There's a plan to bring cookies (to use pesticide to control the beetle population). We're trying to say why the plan will fail at its objective.

If John is not baking as well as he usually does (and who really cares why...) it's less likely his cookies will be as good, and therefore might fail to make the office happy.

If the beetles develop resistance to toxins (and who really cares why...) it's less likely the pesticide will be able to control the beetle population.

AndrewN · Answer

Hello,  SUV0508 . Of course, if beetle larvae are responsible for ultimately  devastating the potato crop , then the beetles themselves are the source of the problem. This question stem requires a careful read. We are asked to SUPPORT  the view that controlling the Colorado beetle by using pesticides to kill its larvae is NOT advisable . In other words, we want to find a compelling reason among the five answer choices provided for farmers not to use pesticides to kill the beetle larvae.

The first two answer choices have nothing to do with pesticides, so we can safely get rid of them. Choice (D) introduces the notion that applying the pesticides is an inconvenience to the farmers, but that has nothing to do with the  effect  of the pesticides: to kill the beetle larvae. Thus, we can discard (D). Choice (E) hinges on a vague  some . That could refer to two beetle larvae, so we have no way of knowing what to make of the information. Choice (C) is the best of the lot because, if the adult beetle  develops a resistance to toxins  (I guess all toxins, since  the toxin  is not mentioned), then it will presumably pass on such resistance to its offspring, since larvae are still beetles. In short, if the beetle is pesticide-resistant and gets to reproduce, and its offspring do the same, and so on, then it would not make sense to use pesticides in an effort to kill the beetle larvae.

Perhaps that makes more sense now. Remember, we are only looking for the best of the five options in relation to the question stem, not an airtight answer.

Good luck with your studies.

- Andrew

The Colorado beetle originally fed on a particular type of plant. Howe

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