Brushing your teeth regularly, no matter which toothpaste you use, wil

I will go with B.
"The fact that brushing will reduce tooth decay does not show that fluorides are of no value."
This looks like a critisism on the passage line "So, you can forget about fluorides:....".

Please post OA.

I think it's B, cos plaque is not necessarily the only thing that could cause tooth decay. Fluorides could help with other factors causing tooth decay.

So if it were to ask about 'weaken the conclusion' , would C be correct?

Hey Vscid,

No, C wouldn't be correct. I didn't mean to imply that different answer choices in the same question could be correct based on the wording, only that the wording will give you a hint to which direction you should go in, so you don't fall for traps. C is still wrong here, because it doesn't address fluoride at all. Even if brushing isn't great, that doesn't help us see that fluoride might be better/as good.

Word.

Argument: Brushing your teeth regularly, no matter which toothpaste you use, will reduce your chances of tooth decay. Scientists have concluded that, when you brush, you reduce tooth decay by removing the film of plaque that forms on teeth and gums. So, you can forget about fluorides: brush your teeth carefully and say goodbye to cavities.

Argument Analysis:
(1) It doesn't matter what toothpaste you use. Just brush your teeth! Brushing your teeth will reduce the chances of getting a tooth decay.
(2) Scientists have (probably) done some research and have concluded that the simple ACT of brushing removes plaque (something not good for your teeth).
(3) The Author concludes that we need to forget about "flourides". Just brush your teeth carefully and don't worry about tooth decay/cavities!

Things to note:
(1) The argument provides us with two conclusions. #1 of the scientists when you brush, you reduce tooth decay by removing the film of plaque and #2 of the authors forget about fluorides: brush your teeth carefully and say goodbye to cavities.
(2) You don't need to know what "fluorides" are (I didn't). All that matters is that the author claims that we don't need fluorides. If this word seems confusing replace it with "X". So we don't need X... cool!

Question Stem: Weaken the argument. Basically we need to go against the conclusion that we don't need fluorides (...X )

Pre-thinking:
1) Well The author says that I don't need fluorides. So if I find an answer choice that says I do need fluorides then I am weakening the argument.

2) I don't really need to say that I NEED fluorides. Even if I come across a choice that says "brushing is not enough to prove that fluorides is not needed" then I'm good. Because notice the author says that we can forget fluorides. So even if we show that we can't be sure about "forgetting" fluorides then we are indeed going against the author.

Analysis:

Okay so Brushing + fluorides is good for the teeth. But is this enough to prove that brushing alone is enough and that we don't need fluorides. Let's take a simple analogy. Let's say Bob has sensitive feet and so he goes to a shoe shop and picks up a shoe with a light + soft sole. The shopkeeper suggests that he should also buy the external "soft+ sole" that he could fit in his shoe for EXTRA COMFORT. So yes, shoe + soft+ sole is good for his feet. But Bob could still decline the offer by saying I can forget the soft+ sole, the shoe itself is enough.

Similarly, Brushing + fluorides is good BUT we could, in the authors words (and what our friend Bob said), forget "fluorides" because Brushing is enough for our teeth, just as how the shoe is enough for our feet! So (A) is out


Hey wait a minute, this reminds me of pre-thinking #2. This choice shows that the entire premise "brushing is good for teeth and that's all we need" is not sufficient to draw a conclusion on another factor "fluorides". Brushing may help reduce tooth decay but is this fact enough to talk about "fluorides". No!

Leets keep (B)


That's good! But how does this show that fluorides is not needed? This choice doesn't even talk about fluorides nor provides with any information to infer anything about fluorides. Irrelevant!


All this choice says is that we humans will always have teeth with some plaque (eww!) But so what? Just like (C), this choice is irrelevant!


Okay, so now we have a choice that mentions "fluorides". Cool so lets hear it out. "Scientists are wrong" hmm... what did scientists say? Lets read the argument Scientists have concluded that, when you brush, you reduce tooth decay by removing the film of plaque that forms on teeth and gums Scientists have spoken about "brushing" "decay" "plaque and where to find it" but they do not comment about fluorides. That is something that out author does. We need to prove the author wrong, not the scientists. Since this choice negates the conclusion of the scientists, it too (like (C) and (D)) is irrelevant!


Correct Choice: B

Takeaway

We don't need to know/understand each and every term in the argument. I had no idea what a fluoride is. But that didn't matter. All I knew is that I had to show: Either that I NEED it Or that at least I CAN'T SAY FOR SURE I don't need it.

Saasingh I hope this helps

Brushing your teeth regularly, no matter which toothpaste you use, will reduce your chances of tooth decay. Scientists have concluded that, when you brush, you reduce tooth decay by removing the film of plaque that forms on teeth and gums. So, you can forget about fluorides: brush your teeth carefully and say goodbye to cavities.

Which one of the following is a criticism of the reasoning in the argument?

(A) Brushing with fluoride toothpaste has been shown to reduce tooth decay. - WRONG. In a way it strengthens the conclusion.
(B) The fact that brushing will reduce tooth decay does not show that fluorides are of no value. - CORRECT. So you need not forget about fluorides since it has got value.
(C) Few people adequately remove plaque by brushing. - WRONG. Few people is problem at first, though what they do is problematic. These people can be exception. which is not at all reasonable to consider.
(D) People have plaque on their teeth most of the time. - WRONG. So, no new information.
(E) Scientists have been wrong about fluorides. - WRONG. This additional info does not impact the conclusion at all. Wrong about fluorides in what way!!? Nothing conclusive is inferable.

Answer B.

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