During the recent spate of brushfires in the Southwest, homeowners who

Question

During the recent spate of brushfires in the Southwest, homeowners who lived near affected areas were advised to douse their roofs with water to prevent their houses from catching fire, before evacuating the area. After the fires were brought under control and the homeowners were allowed to return to the area, many who doused their roofs discovered significant fire damage to their houses. Clearly, then, dousing their roofs was a wasted effort.

Which of the following, if true, would most weaken the conclusion above?

A. The houses of owners who did not douse the roofs with water suffered appreciably more fire damage than did those of owners who did douse the roofs with water.

B. Not all homeowners who doused their roofs did so to the same extent.

C. The fire insurance rates for those who doused their roofs did not increase after the fire.

D. The houses that suffered the least damage were those in which the owners remained and continuously doused the roofs.

E. Most of the homeowners who doused their roofs had been through a brushfire evacuation before.

pratham1911 · Answer

im confused between a and d pls help

PyjamaScientist · Answer

Hi  pratham1911 ,
The conclusion here is- "  Dousing roofs was a wasted effort  ". That is- People who doused their houses got  no benefit  out of their actions. If we can  accrue some benefit  to their act of dousing their roofs with water, then the conclusion that it was "a wasted effort" will be weakened. (A) does that nicely by showing that people who doused their roofs with water suffered less damage to their houses as compared to the ones who did not. Hence, it was  not a wasted effort   as the conclusion says. And thus, (A) is the right choice.
(D) on the other hand, speaks just about the houses that suffered the least damage. What if such houses were only 1% of the total houses? Then, this 1% data can not speak for the majority. (A), on the other hand, compares the " houses of owners who did not douse the roofs with water " with the " houses of the owners who did douse the roofs with water ". Thus, (A) helps us form a majority point of view and thus triumphs over (D).

Hope it helps.

Bunuel · Answer

OFFICIAL EXPLANATION

The conclusion of the argument is that dousing the roofs with water was a wasted effort. The basis for this claim is that the houses of those who doused their roofs still suffered fire damage. We are asked to weaken this conclusion; we could do so by showing that dousing the roofs did provide some positive effect.

(A) CORRECT.  This choice provides a positive effect enjoyed by those who doused their roofs with water: if they hadn't, the homes would have suffered even more damage.

(B) This may be true, but it does not show that those who doused their roofs did enjoy some positive result.

(C) This is irrelevant to the argument; it does not address the extent of the damage and it occurs after the incident described in the argument.

(D) While this may be true, it does not address those who doused their roofs and then left, the specific effort discussed in the passage. We still have not shown that those who doused and left did not waste their time.

(E) This is irrelevant to the argument; it does not address the extent of the damage.

devil.rocx · Answer

Conclusion - Dousing their roofs was a wasted effort.
Possible Answer Choice - Maybe this wasn't a wasted effort.

A- Cleary tells us why it wasn't a wasted effort. 
B- Breaking the premise itself and not addressing the issue. 
C- Irrelevant 
D- This is a different group of people. This can be true but it doesn't address the problem of people who doused and left the house, right? 
E- Irrelevant

agrasan · Answer

Hi  KarishmaB   MartyMurray

Can we say that (D) is wrong mainly because it brings  another class of people who remain in houses  rather than leaving their houses? Thus, that class is not very relevant for us to undermine the conclusion.

AbhishekP220108 · Answer

Hi  agrasan  let me try to help

D. The houses that suffered the least damage were those in which the owners remained and continuously doused the roofs.-As per D yes it brought the set of people that has not been considered while reaching on the conclusion. Argument presented the info of people who has to evacuate after dousing the roof with water, whether some stayed and continuously doused is not going to affect the conclusion

KarishmaB · Answer

The conclusion says that dousing was not effective since even after dousing there was damage. We weaken it by comparing the damage with those who did not douse. If they saw a lot more damage, then we know that dousing was useful. It reduced damage. 
Option (D) says that continuous dousing is more effective. That doesn't weaken that dousing is not effective. If anything, it says dousing is effective and the more you douse, the less the damage.

agrasan · Answer

Thanks  KarishmaB 
So we have to indirectly say that  dousing is effective.

I am still confused why (D) is wrong, if you say about (D) in your reasoning   If anything, it says dousing is effective and the more you douse, the less the damage    then it does strengthen the conclusion by indicating that  dousing is effective.  
 Please let me know where I am faltering to understand.

KarishmaB · Answer

The author's conclusion is " dousing their roofs before evacuating was a wasted effort."

To weaken it, we have to say that dousing was not a wasted effort. It had some positive impact.  
 Option (A) compares no dousing to the one time dousing - that those owners who did not put any water suffered more damage. So it means that dousing once was effective in reducing the damage. Hence (A) is correct.

Option (D) says that more dousing led to lower damage. So it is showing that more dousing is more effective, but it does not tell us whether the one time dousing was a wasted effort or not. That is why (D) is incorrect.  
 (I think my thought process got bungled up there at the end!)

agrasan · Answer

Thanks very much, am clear now.

During the recent spate of brushfires in the Southwest, homeowners who

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