A recreational airplane manufacturer's advertisement states, "The

Logical leap of faith.

The plane is the safest in its class, so it must be the safest in all classes of planes.

Lets assume that the class that this plane pertains to is also the safest class.

C weakens the assumption, because C states that the class that the plane pertains to is not the safest one.

Premise : the recreational AZ121 aircraft has the fewest fatalities per crash landing of any aircraft in its class.
Conclusion : the AZ121 is one of the safest planes available today.
Only C weakens properly the argument since it assimilates recreational aircraft as dangerous aircraft and Thus, makes the argument weak.

Premise: There is a statistical evidence that if AZ121 crushes then number of fatalities in the crash will be less than number of fatalities in a crash case of another airplane of the same class.
Conclusion: AZ121 is one of the safest airplanes.
Assumption: Definitely, a number of requirements should be assessed to evaluate safety of a plane and the most obvious requirements are: Fatalities per crashes level (how many fatalities for 1000 crashes) and Crashes per flights level (how many crashes for 1000 flights).
We should note, that there is no relation between "Fatalities per crashes" ratio and "Crashes per flights" ratio.

A - the statistics of fatalities per crashes for other class planes evidences that AZ121 plane's fatalities per crashes ratio could compete even with this ratio of other class planes. Since there is no information about crashes per flights in the statement, we can't make conclusion about safety of the plane.
B - it's not interesting for us whether the model is new or not as a new one could be ether perfect in terms of safety or hopelessly bad.
C - there are a lot of crashes per flights in recreational class, so crashes per flights ratio for AZ121 is higher than it's for other planes. The good news is that majority of all crashes (relatively) end without fatalities, but anyway the plane can not be called "safe" - WEAKEN THE ARGUMENT
D - restatement of the premise, no connection with the conclusion of the argument.
E - neutral statement, no connection with the conclusion of the argument.

Read the highlighted portion. Author presents statistic about one class of plane and moves to conclude that it is the safest of all the planes. Generalization error. Hence C is the correct answer.

Consider kudos if my post helps!!

Archit

i didn't get it.
Conclusion : The advertisement goes on to claim that the AZ121 is one of the safest planes available today.
It only states that its 'One of the safest' plane

Option C states

Recreational aircraft are more likely to be involved in crash landings than are other types of airplanes.

From the premise we have: that number of fatalities /crash is the lowest for AZ121 in its class. So even if number of crash landings are higher fatalities are low as compared to any other planes in its class.
How does it attack the conclusion its one of the safest plane. Even with highest incidence of crash landings, fatalities are low. Doesn't it strengthen the argument?

THIS IS A EASY ONE....NSTB SAYS THAT AZ121 HAS FEWER FATALITIES PER CRASH LANDING OF ANY AIRCRAFT OF ITS CLASS, HENCE IT IS THE SAFEST.....
FEWER FATALITIES ONCE CRASHED IS FINE BUT WHAT IF IT KEEPS CRASHING AND ADDING TO ITS TOTAL NUMBER OF FATALITIES...

HENCE C

C weakens by showing a way in which the stat used (lowest fatalities per crash) might not prove that the plane is safe. What if the AZ121 only has 1 fatality per crash, but it crashes on 90% of its flights? You wouldn't call it very safe. It'd be like me saying "I am awesome at quant because I only miss 1 question per practice session". You'd also need to know how many questions I do per session to know if that stat is meaningful.

Indeed,
The argument does a slight of hand by implying that least number of fatalities per crash land = safe
What it fails to let us know is whether the air planes generally crash-land more often than do other airplanes.

If it is found that they do crash land more often, the conclusion - that they are one of the safest- will be broken.

Option C is therefore the appropriate response.
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Ad

A recreational airplane AZ121 aircraft has the fewest fatalities per crash landing of any aircraft in its class.

The claim is that the AZ121 is one of thesafestplanes available today.



Which of the following, if true, most seriously weakens the argument in the advertisement?

A. THE NTSB listed many planes in other classes that had more fatalities per crash landing than did the AZ121.
Opposite. Strengthens the conclusion. We need weakener here.

B. Despite its popularity, the AZ121 is a relatively new aircraft, only having been sold on the market for two years.
Duration out of concern, even its time period is within 2 yrs it can be good. Out of scope.

C. Recreational aircraft are more likely to be involved in crash landings than are other types of airplanes.
This hints that even it is better than few places in its own class, the whole company products are dangerous. the only Weakener

D. The rate of fatalities per crash landing of the AZ121 is more than five times lower than the next highest rate of fatalities per crash landing in its class.
Same as B. Opposite.

E. The NTSB issues its safety reports on a monthly basis.
timely reporting is out of concern. OFS

Level 650-700

All the answer choices are background info irrelevant of the argument and its conclusion except for answer C;
AZ121 is the best in its series in the recreational category of airplanes ,
however, the recreational airplane might have only one engine contrary to the travel airplanes (airbus,boing etc..) which consist in general of 2 engines rendering a superior safety in flights (ok i am just inferring here i am not an aerodynamic plane expert).

C. Recreational aircraft are more likely to be involved in crash landings than are other types of airplanes.

fewest fatalities per crash landing , but a lot more crash landings

Official Explanation:

Correct Answer: C

The correct answer to this question is (C). This is a Weaken question, requiring the test taker to choose the correct answer that provides information that refutes, or casts doubt upon, the claim that the AZ121 is one of the safest planes currently available. (A) is incorrect because it strengthens, rather than weakens, the conclusion. (B) is incorrect as is out of Scope; that the AZ121 is relatively new on the market and is popular is not related to it being one of the safest on the market. (C) This is the correct answer, which properly recognizes a weakness in the argument; specifically, simply because the AZ121 has the fewest fatalities out of a class of aircraft that has the most crash landings does not make it the safest aircraft out of all classes. (D) is incorrect as is out of Scope; the rate within the class, already knowing that it is the lowest in the class, does not weaken the conclusion; (E) is incorrect as is out of Scope; the frequency of reports has no effect on the conclusion.

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