The ice on the front windshield of the car had formed when moisture

Question

The ice on the front windshield of the car had formed when moisture condensed during the night. The ice melted quickly after the car was warmed up the next morning because the defrosting vent, which blows on the front windshield, was turned on full force.

Which of the following, if true, most seriously jeopardizes the validity of the explanation for the speed with which the ice melted?

(A) The side windows had no ice condensation on them

(B) Even though no attempt was made to defrost the back window, the ice there melted at the same rate as did the ice on the front windshield.

(C) The speed at which ice on a window melts increases as the temperature of the air blown on the window increases.

(D) The warm air from the defrosting vent for the front windshield cools rapidly as it dissipates throughout the rest of the car.

(E) The defrosting vent operates efficiently even when the heater, which blows warm air toward the feet or faces of the driver and passengers, is on.

arhumsid · Accepted Answer

Its causal:  defrosting vent was turned on (cause) ==> Ice melted  quickly  (effect)

we need to  weaken  this causality.
We need to show that the Rate at which the ice on the front windshield melted was was independent of the effect of the defrosting vent.

B does exactly that.

Nevernevergiveup · Answer

The ice on the front windshield of the car had formed when moisture condensed during the night. The ice melted quickly after the car was warmed up the next morning because the defrosting vent, which blows on the front windshield, was turned on full force.

Which of the following, if true,  most seriously jeopardizes the validity of the explanation for the speed with which the ice melted ?

A. Does not affect the conclusion

B. Weakener 
 
C. strengthener

D. what happens after defrosting is not needed. OFS

E. when The defrosting vent operates efficiently is out of concern. OFS

BhishmaNaidu99 · Answer

TO weaken this conclusion we need to say that , the vents are not the reason for the speed of ice melt,

A. Side windows has no ice and is not related to ice melt , so irrelevant.
B. This option say there is some other reason for the ice melt, as ice on rear window melted at same rate without any vents. CORRECT 
C. How the rate of ice melts is not related to the vents here. Irrelevant.
D. What happens to the vent air after is also not required for our discussion,Irrelevant. 
E. when does the vents operate efficiently is not what we want, we want that vent is not involved to weaken the statement.

mba757 · Answer

Conclusion : “The ice melted quickly after the car was warmed up the next morning (because the defrosting vent, which blows on the FRONT windshield, was turned on full force)”
 Prethink : Was it only the front that defrosted? What if the sides or back defrosted just as quickly?
 Which of the following, if true, most seriously jeopardizes the validity of the explanation for the speed with which the ice melted?
 
 (A) The side windows had no ice condensation on them
 Irrelevant. There’s no ice on the sides. It wouldn’t help further the claim in which it describes a vent that melts using a defrosting vent.

(B) Even though no attempt was made to defrost the back window, the ice there melted at the same rate as did the ice on the front windshield.
 This weakens the claim because it shows that there could be some other external force that’s warming the car. We know the defrosting vent is on the front. But if there’s no defrosting vent in the back (and there’s no attempts to defrost in the back) AND ice melted at the same rate as did the ice on the front then it undermines the claim that it was JUST the defrosting vent in the front.

(C) The speed at which ice on a window melts increases as the temperature of the air blown on the window increases.
 Opposite trap – strengthener, if anything. It essentially further substantiates the claim that it could be the defrosting vent (presumably, the defrost vent would increase the temp to melt the ice).

(D) The warm air from the defrosting vent for the front windshield cools rapidly as it dissipates throughout the rest of the car.
 Opposite trap – strengthener, if anything. It essentially further substantiates the claim that it could be the defrosting vent that made the front melt really quickly, while the other sides of the car presumably didn’t

(E) The defrosting vent operates efficiently even when the heater, which blows warm air toward the feet or faces of the driver and passengers, is on.
 Out of scope trap – we don’t care about the heater. We want to know the impact of the DEFROSTING VENT in relation to the front windshield.

haithamnimer · Answer

You need to attack the assumption mentioned in the argument " the ice melted quickly after the car was warmed up the next morning because the defrosting vent, which blows on the front windshield, was turned on full force"   by saying that there is another factor which helped in removing the melted ice which is below:

(B) Even though no attempt was made to defrost the back window, the ice there melted at the same rate as did the ice on the front windshield.

Here, there is no air blowing on the back window, but the ice melted, thus, there is another factor helping in melting the ice!

stackskillz · Answer

Conclusion  - Defrosting vent melts the ice on the front windshield. 
 Type  - Weaken

(A)  The side windows had no ice condensation on them  - Why did the side windows have no condensation? Maybe the moisture in the air condensed on the front windows instead or maybe waxing the side mirrors made them resistant to mositure depositing on them post condensation. Whatever the case, this doesn't help us explain whether the defrosting vent melted the ice on the windshield.  Drop

(B)  Even though no attempt was made to defrost the back window, the ice there melted at the same rate as did the ice on the front windshield.  This defintely shows that the effect occurs even without a cause. This defintely hurts the reasoning.  Keep

(C)  The speed at which ice on a window melts increases as the temperature of the air blown on the window increases.  This slightly supports the conclusion by explaining an attribute of the defrosting process.  Drop

(D)  The warm air from the defrosting vent for the front windshield cools rapidly as it dissipates throughout the rest of the car.  Does the warm air from the defrosting vent defrost the windshield. No idea.  Drop

(E)  The defrosting vent operates efficiently even when the heater, which blows warm air toward the feet or faces of the driver and passengers, is on.  Just drop. Not relevant.

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The ice on the front windshield of the car had formed when moisture

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