Dutch elm disease, which is caused by the fungus C. ulmi spread by

Question

Dutch elm disease, which is caused by the fungus C. ulmi spread by adult scolytid beetles, has already destroyed 70 percent of the elms in Greenwood Forest. Another naturally occurring fungus, P. oblonga, kills larvae of the scolytid beetle. Forest rangers plan to introduce P. oblonga into Greenwood Forest in order to save the remaining mature elms.

Which of the following, if true about P. oblonga, provides the strongest evidence that the plan will succeed?

(A) It is spread by a variety of birds that nest in trees that are the home of scolytid beetle larvae.
(B) It has been known to lie dormant within a tree for up to ten years before it begins to reproduce.
(C) It spreads more slowly than C. ulmi, under most climatic conditions.
(D) It does not destroy some commonly found subspecies of scolytid beetles.
(E) It has been known to kill maple trees by destroying their root systems

This question is different from  the other question  with same prompt. Please read carefully.

TaN1213 · Accepted Answer

SB spreads C.U---> killed 70% of elms
What can stop SB? ------> P.OB
Result: Can save the remaining elms

Type: Strenghten
Prethinking: 1. Anything that speeds up the process
2. Killing SB doesn't lead to any other way that would kill elms.
3. Any support that indicates that killing of SB is easy and viable.

Option choices:

(A) It is spread by a variety of birds that nest in trees that are the home of scolytid beetle larvae. --->  Prethinking 1 in action 
(B) It has been known to lie dormant within a tree for up to ten years before it begins to reproduce.  Out of scope 
(C) It spreads more slowly than C. ulmi, under most climatic conditions.  Opposite of prethinking1-->weakens 
(D) It does not destroy some commonly found subspecies of scolytid beetles. --> Weakens 
(E) It has been known to kill maple trees by destroying their root systems --->  Can it be any more out of scope?

bunny12345 · Answer

Option A. This question is like selecting the lesser evil among the options. Argument says that P. oblonga kills larvae of beetles. Rangers plan to introduce them in Greenwood forest to save elms. We have to provide strongest evidence.
If we look at options, Options B, D, and E are highly irrelevant to the problem at hand. Option C says P. oblonga spreads slow, but this is also irrelevant since Rangers are already going to introduce them in the Forest. So, spreading is not the issue.
Hence, we are left with Option A. Since these are already spread by birds to keep the nests safe, spreading might work. Hence A is the answer

vasuca10 · Answer

bunny12345  I would differ with your reasoning given for selecting Option A. We have to select an answer choice that makes killing of SB easy and also speeds up this process. As per Option A P-Oblonga is spread by variety of birds that nests in trees which is home of SB. Hence this will speeden up the process of killing SB as P-Oblonga shall be able to spread fastly and thus we would be able to save remaining of the elms

Kurtosis · Answer

Question Type: Strengthen

Argument: P. oblonga kills larvae of the scolytid beetle. So, forest rangers plan to introduce P. oblonga to save the remaining elms.

(A) It is spread by a variety of birds that nest in trees that are the home of scolytid beetle larvae. - Since P. oblonga is spread by birds, it aids the process to kill the larvae of scolytid beetle.

(B) It has been known to lie dormant within a tree for up to ten years before it begins to reproduce. - Weakens

(C) It spreads more slowly than C. ulmi, under most climatic conditions. - Irrelevant

(D) It does not destroy some commonly found subspecies of scolytid beetles. - Weakens

(E) It has been known to kill maple trees by destroying their root systems - Irrelevant

Answer: A

shoumkrish · Answer

Dutch elm disease, which is caused by the fungus C. ulmi spread by adult scolytid beetles, has already destroyed 70 percent of the elms in Greenwood Forest. Another naturally occurring fungus, P. oblonga, kills larvae of the scolytid beetle. Forest rangers plan to introduce P. oblonga into Greenwood Forest in order to save the remaining mature elms. 
Which of the following, if true about P. oblonga, provides the strongest evidence that the plan will succeed?

(A) It is spread by a variety of birds that nest in trees that are the home of scolytid beetle larvae.  Correct . 
(B) It has been known to lie dormant within a tree for up to ten years before it begins to reproduce.  Weakens .
(C) It spreads more slowly than C. ulmi, under most climatic conditions.  Weakens. 
(D) It does not destroy some commonly found subspecies of scolytid beetles.  Weakens. 
(E) It has been known to kill maple trees by destroying their root systems  Out of scope.

bronaugust · Answer

To solve this question, you may follow the    IMS's four-step approach   .

STEP #1  - FIGURE OUT THE QUESTION TYPE BY READING THE QUESTION STEM

The stem says, 'Which of the following, if true about P. oblonga, provides the strongest evidence that the plan will succeed?' Clearly, we are dealing with a strengthening question. Now that you have figured out the question type, you may move on to the second step.

STEP #2  - DECONSTRUCT THE ARGUMENT

In a strengthening question, it is a must to deconstruct the argument by figuring out the premise and the conclusion. The plan itself is the conclusion; the basis on which the plan is formulated becomes the premise.

CONCLUSION:   Forest rangers plan to introduce P. oblonga into Greenwood Forest in order to save the remaining mature elms.

PREMISE:   A naturally occurring fungus, P. oblonga, kills larvae of the scolytid beetle,     which spreads fungus C. ulmi, and this fungus causes Dutch Elm disease, which has already destroyed 70 percent of the elms in Greenwood Forest.

STEP #3:  FRAME A SHADOW ANSWER/KNOW WHAT THE RIGHT ANSWER SHOULD BE DOING

In a planning question, an option that strengthens the argument simply states a situation that will help the the plan become successful. You may now proceed to the final step.

STEP #4:  ELIMINATE INCORRECT ANSWER OPTIONS

Answer options that do not impact the argument or those that weaken the argument can be eliminated.

(A)  It is spread by a variety of birds that nest in trees that are the home of scolytid beetle larvae. -   STRENGTHENS   -  As per the premise, P. Oblonga kills larvae of the scolytid beetle, so if it is spread by a variety of birds that nest in trees that are the home of scolytid beetle larvae, the larvae will be killed, meaning they will not be able to spread the fungus that causes the disease. The remaining mature elms will therefore be saved.  -   KEEP

(B) It has been known to lie dormant within a tree for up to ten years before it begins to reproduce. -   WEAKENS   -  If it lies dormant for ten years, it will not be fast enough to prevent the spread of scolytid beetles, so by the time it begins to reproduce, the elms are very likely already affected by the disease.  -   ELIMINATE

(C) It spreads more slowly than C. ulmi, under most climatic conditions. -   WEAKENS   -  If it spreads more slowly that C. ulmi under most climatic conditions, the elms may end up getting afflicted by the Dutch elm disease caused by C. ulmi before P. oblonga creates an impact.  -   ELIMINATE

(D) It does not destroy some commonly found subspecies of scolytid beetles. -    WEAKENS   -  If it does not actually destroy some commonly found subspecies of scolytid beetles, those subspecies may multiply, spreading fungus C. ulmi that causes the stated disease. -    ELIMINATE

(E) It has been known to kill maple trees by destroying their root systems. -   OUT OF SCOPE   -  Not worried about whether or not it kills maple trees!  -   ELIMINATE

Hence, A is the right answer.

Utkarsha20 · Answer

(A) is CORRECT: It provides the delivery mechanism. If birds carry the fungus directly to the larvae’s home, the plan is physically feasible.

(B) & (C) are WRONG: "Too slow." If the fungus is dormant for 10 years or spreads slower than the disease, the trees die first.

(D) is WRONG: We are concerned with destroying the larvae and even so it is a weakener

(E) is WRONG: Killing maples doesn't tell us if the elms will be saved.

Dutch elm disease, which is caused by the fungus C. ulmi spread by

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