Remember that a premise is necessary for a conclusion if the falsity of the premise guarantees or brings about the falsity of the conclusion. First, we check to see if the answer choice strengthens the passage, and then, if it does strengthen, we negate the answer choice to see if its negation makes the argument fall apart. If the answer choice does both those things, then it is our correct answer.
The conclusion of the argument is "the airlines should rethink their training approach to reducing commercial crashes." Why? Studies have shown that pilot error contributes to two-thirds of all such crashes. To address the problem, the airlines have upgraded their training programs by increasing the hours of classroom instruction and emphasizing communication skills in the cockpit. However, the passage states that it is unrealistic to expect that these measures alone will compensate for pilots' lack of actual flying time.
It's important to note that we are focusing specifically on the two-thirds of all crashes that are caused by pilot error.
Now let's discuss the difference between answer choice (C) and (D):
Answer choice (C) does somewhat strengthen the argument. If it is true that if pilot training programs focus on increasing flying time, then the number of airline crashes will decrease, then this technically supports the conclusion that the airlines should rethink their training approach to reducing commercial crashes due to the fact that the current training programs are not compensating for lack of flying time. However, remember that we are focusing specifically on the two-thirds of all crashes that are caused by pilot error, not overall crashes. For this reason, it doesn't destroy the argument when negated: "The number of airline crashes will not necessarily decrease if pilot training programs focus on increasing actual flying time." So what? As long as the number of crashes caused by pilot error decreases, this argument would still stand. So, this is not our answer.
Answer choice (D), however, is both required and strengthens. If lack of actual flying time is an important contributor to pilot error, then it would strengthen the argument to recommend including it in the training program. More so, the negation is as follows: "Lack of actual flying time is not necessarily an important contributor to pilot error in commercial plane crashes." Well, if it isn't an important contributor, then why should airlines rethink their training approach to reduce commercial crashes caused by pilot error? The negation of (D) makes the argument fall apart, so this is our answer.
Hope that was helpful! Please let us know if you have any other questions.
BatmanNovember 22, 2013
Thanks always!!!! You guys are superb!!!!
erojasNovember 5, 2017
Why is A incorrect?
MehranNovember 14, 2017
@erojas the conclusion of the argument is "the airlines should rethink their training approach to reducing commercial crashes."
Why? Studies have shown that pilot error contributes to two-thirds of all such crashes. To address the problem, the airlines have upgraded their training programs by increasing the hours of classroom instruction and emphasizing communication skills in the cockpit. However, the passage states that it is unrealistic to expect that these measures alone will compensate for pilots' lack of actual flying time.
(A) definitely seems to strengthen the argument by point out that training programs can impact pilot errors (i.e. so rethinking the training program can have an impact).
But notice that when you negate (A) it also strengthens the argument that "the airlines should rethink their training approach to reducing commercial crashes" (i.e. because training programs cannot necessarily eliminate pilot errors).
Hope that helps! Please let us know if you have any other questions.
nelsonOctober 22, 2018
Couldn't we apply the way of thinking about C ("The number of airline crashes will not necessarily decrease if pilot training programs focus on increasing actual flying time." So what? As long as the number of crashes caused by pilot error decreases, this argument would still stand.) to D? The fact that Flight time is not an important contributor to pilot error does not mean that is not a contributor. Thus, if flight time could be a contributor then why shouldn't airlines rethink their approach.
The reason I'm bringing this up is that it seemed to me that the reasoning for eliminating C was, in my opinion, so nit picky that it could be applied to D in the same way and make them both wrong.
Irene-VeraApril 19, 2019
I'm sorry, I don't really understand how C is incorrect after reading this. I was in between D & C. Can I possibly get another explanation? thank you.
dannyodFebruary 8, 2020
Bumping this, I still don't understand how the negation of D invalidates the conclusion any more than the negation if C does. Additional help would be appreciated. thanks!
ElizabethGlassmannJuly 1, 2020
What you are saying is, due to the there being only two-thirds of such crashes makes it not sufficient because it does not encompass ALL. Therefore, when we negate the word WILL, we use "not necessarily". Am I correct?
shunheJuly 3, 2020
Hi @Irene-Vera, @dannyod, and @ElizabethGlassmann,
Thanks for the question! This one is an extremely tough question for sure because of the ways answer choices C and D interact. Here’s the thing about (C): when you negate it, it weakens the argument. Not doubt about it. But now think about what has to be true for (C) to be true. (C) tells us that if pilot training programs focus on increasing actual flying time, the number of airline crashes will decrease. OK. Is this answer choice itself relying on any assumptions? Well, (C) can only be true if increasing actual flying time decreases pilot error (which contributes to two-thirds of crashes). If increasing actual flying time doesn’t decrease pilot error, then (C) wouldn’t be true. But look at what (D) says. It says that lack of actual flying time is an important contributor to pilot error in commercial plane crashes. That’s what we said (C) depends on! (C) assumes (D), basically. And since we have one answer choice that assumes another more basic one, that more basic answer choice is going to be the correct answer (since (C) is essentially that assumption with more added on).
Also, in general, when we negate “this will that,” yes, we generally negate it as “this won’t necessarily that.” The negation of “Pressing the button will turn the sprinklers on” is “Pressing the button won’t necessarily turn the sprinklers on.”
Hope this helps! Feel free to ask any other questions that you might have.
