More selective than most chemical pesticides in that they ordinarily d

the passage is easy to read and understand. but to answer questions requires you to find out the place in the passage, which yield the information in the correct answer. positioning the place is time consuming and require patience. if you are hurried, you die. once you find the place, you can be confident with your choice.

the challenging is the fine the place in the passage dense with details and information.

SajjadAhmad

Hi mate, there are multiple typos in the OP

Q3 E should be "with a larger species"

Q4 E should be "occur"

Question 3 asks us to identify which choice is mentioned in the passage as an indirect effect of using a biocontrol agent.

Here's choice (B):


This choice does not state any example outright, so we shouldn't fill in that information as a reason for keeping the choice around.

Instead, (B) tells us that the unintended proliferation of a nontarget animal species is an indirect effect of using a biocontrol agent. Proliferation means rapid increase, and there's no evidence for that taking place in the passage:

• The highlighted example describes what happened when rabbits were targeted by a biocontrol agent.
• After the biocontrol agent (a virus) was introduced, two nontarget animal species were affected: ants and blue butterflies.
• The indirect effect on ants was that underground ant nests were reduced.
• The indirect effect on the blue butterfly was extinction.

Reduction goes in the opposite direction of proliferation, and extinction is basically as far as you can get from proliferation. This is why (B) must be eliminated.

Here's choice (D):


Again, this choice does not state any example outright, and never mentions the butterfly. We need to be precise when confirming whether this matches the passage.

Fortunately, when we check the passage, choice (D) is a spot-on match for what the author has written:


This is why we keep (D) as the correct choice.

I hope this helps!

WHY in Q-6 answer cant be B?
Kindly clarify?

Please check out this post and let us know if you have further questions.

I hope that helps!

this scenario is called "easy passage, close answers".
in this situation, we well meet an easy passage , which we can understand it with easy. but the questions are hard, specifically, the questions 2,3 and 4, contain 2 answer choices which are close. both these choices look correct but one of them contain ONE wrong word. realizing to find ONE WRONG WORD is key

Question 3, why can't it be option E?

Can someone explain why Q3 option E is incorrect? is it because the passage only says that bio-control agents compete with non-target species for resources and not "larger species" per se?

Q4. Why is option E wrong?

Q5. Is option B wrong because the passage does not mention anything about bio-control agents having "direct adverse effects"?

That's right! The author tells us that biocontrol agents can negatively affect nontarget species by competing with them for resources. However, the author NEVER mentions larger species. That's why we eliminate (E).

Question 4

Here's the highlighted text that Q4 asks us to analyze:

Another example of indirect negative consequences occurred in England when a virus introduced to control rabbits reduced the amount of open ground (because large rabbit populations reduce the ground cover), in turn reducing underground ant nests and triggering the extinction of a blue butterfly that had depended on the nests to shelter its offspring.

In this scenario, the introduction of a biocontrol agent (a virus to control rabbits) led to a change in habitat (less ground cover), which in turn suppressed an unrelated structure in that habitat (underground ant nests), which in turn led to the extinction of a nontarget species (blue butterfly) that depended on the structure to survive (using the ant nests to shelter butterfly offspring).

Choice (E) states that this example most clearly serves to illustrate "the way in which indirect consequences from the use of biocontrol agents are most likely to occur."

But is the author trying to show us that indirect consequences of biocontrol agents most likely happen in this way?

• Biocontrol agent for species A changes habitat
• Change in habitat suppresses an unrelated structure built by species B
• Suppression of unrelated structure leads to extinction of species C

Nope! This is simply one of many ways that indirect consequences can occur. The highlighted example is preceded by a description of a different scenario and followed by an admission that we lack information about extinctions and disruptions resulting from indirect interactions.

That's why we eliminate (E). Choice (B) remains the most accurate description of why the author brings up this highlighted example.

Question 5

Let's make sure we're 100% clear on what the question is asking:

5. According to the passage, which of the following is a concern that arises with biocontrol agents but not with chemical pesticides?

The correct answer choice will reflect what the author tells us is a concern that DOES arise with biocontrol agents but DOES NOT arise with chemical pesticides. And the passage gives us our answer pretty explicitly:

...unlike a chemical pesticide, a biocontrol agent may adapt in unpredictable ways so that it can feed on or otherwise harm new hosts.

The correct answer choice should also identify this specific difference: Biocontrol agents can adapt in unpredictable ways, while chemical pesticides cannot adapt. Choice (C) is the only choice that matches up, which is why we keep it.

Now, here's choice (B) again:

(B) Biocontrol agents are likely to have indirect as well as direct adverse effects on nontarget species.

You're right to point out that the author never mentions whether biocontrol agents have direct adverse effects on nontarget species. However, we can also eliminate (B) based on the fact that this choice does NOT identify what the author plainly tells us is a key difference between biocontrol agents and chemical pesticides.

I hope this helps!

Can someone please help me with explanation of question 1?

Thanks for your help.

Posted from my mobile device

Please read earlier response in below link

https://gmatclub.com/forum/more-selecti ... l#p1395308

Hope it helps

Would you please explain how (A) is correct? minustark

Posted from my mobile device

Too many rabbits >>> lost of vegetation or ground cover
To control those rabbits>>> introduction of virus
Virus reduced the rabbits >> so now more ground cover and less open ground (too much grassland)
Ants need open ground for their nests (less vegetation is preferred for ant nests)
And blue butterflies need ant nests
So, the less ground cover or vegetation, the better for our blue butterfly. And since rabbits helped to keep more open grounds, their survival was required for the butterflies.

It took me a while to differentiate B vs E.
E is one way how indirect consequence is most likely to occur. The example given is one way that matches to E
B says what is the intention of author to use this example.
So B matches the question asked.

pretty close

Thanks GMATNinja forQ4 clarification

How is open ground linked to ground cover(vegetation)? when a virus is introduced, it reduced the amount of open ground? What does this mean?
I understand the point that when virus is introduced, rabbits die and hence ground cover increases because rabbits consume ground cover
when a virus introduced to control rabbits reduced the amount of open ground (because large rabbit populations reduce the ground cover),

For Question 2 - Look at this part of the passage - Moreover, determining the potential risks of biocontrol agents before they are used is difficult, especially when a nonnative agent is introduced. So, between the native and non-native, non-native is difficult to predict. Now let's look at option E - The risks of using native biocontrol agents may be easier to predict than those of nonnative biocontrol agents. The word easier is deceptive. Easier doesn't mean it's easier in general. It says between the two, it's easier. Other options, A and C, are not even mentioned in the passage.

For question 3 - We are being asked -the "indirect effect." Look at option D - Diminution of the positive effects conferred by a nontarget animal species. It matches the passage - "a biocontrol agent might reduce the benefits conferred by a desirable animal species." Option E is misleading as the passage never spoke about the "LARGER" species. Moreover, we are looking for an "indirect effect."