Using computer techniques, researchers analyze layers of paint that li

I would go with E.

A. If there are no records available, then indeed the sceptics could use this fact to strengthen their argument that Leonardo didn't paint any mountains. and since there are no records, who knows for sure. NOPE
B. B says that it is "common" for painters to paint mountains. this doesn't make it so that Leonardo did. it was just something that was done customarily. No proof here. NOPE
C. If no one knows which parts were painted between Leonardo and his assistant, it would be difficult in figuring out who painted what part. indeed, its possible that a mountain has been painted. but, again, there is no proof of such. NOPE
D. this just completely strengthens the argument.
E. This is the only one that attacks the "x-ray" argument being made and shows the possible limitations of using the x-ray on the Mona Lisa.

on another note:
"mona lisa/can i get a date on friday/and if your busy, i wouldn't mind taking saturday-ay-ay-ay-ay-ay"
Kudos to anyone who remembers/knows that song. lol.

Here the skeptics are stating that X-rays show no mountainous views.
This objection needs to be weakened. E is the only stmt that weakens X-rays. (I've used simple english)
IMO:
(E) Analysis relying on X-rays only has the capacity to detect lead-based white pigments in layers of paint beneath a painting’s surface layers.

B) Painters of da Vinci’s time commonly created images of mountainous scenery in the backgrounds of portraits like the Mona Lisa - This stmt does not weaken the X-ray equipment. It only "strenghtens" the first claim of the question.

HTH.

(E) Analysis relying on X-rays only has the capacity to detect lead-based white pigments in layers of paint beneath a painting’s surface layers.

Modifier problem here. Its saying that analysis that relies on x-rays only can detect lead-based white pigments. Ok so what else can it detect?

I would have chosen E if it said
Analysis relying on X-rays has the capacity to only detect lead-based white pigments in layers of paint beneath a painting’s surface layers.

Stupid question.

I feel B is also convincing. Even it weakens the skeptic's objections that X-ray examinations of the Mona Lisa do not show hidden mountains.

I do not trust choice E completely as we are not sure of the kind of colored pigments used to paint the mountains behind mona lisa. If lead-based white pigments had been used, then skeptic's objections would have been more strong.

Any help?

How B is the possible explanation ?? is clearly impossible.

The objection talks about X-ray that sheds no light on something: in this case the same Xray says that under the surface of the painting there is nothing.........

E weakens this conclusion saying that: Analysis relying on X-rays only has the capacity to detect lead-based white pigments in layers of paint beneath a painting's surface layers.

From this we certainly know that X-rays in this case do something more than that skeptics sustaine or assert

B says that other painters other than Vinci depicted scenarios using the same landscape of Monna Lisa's (or something, is not so important). Is completely far aways bur really miles away from the correct answer.

Hope this helps

I put your doubts in a spoiler, not to spoil the process of solving the question for other members of the forum.

My approach:
Skeptics say that X-ray do not show hidden mountains -> we need to weaken this statement.
we can do so by proving that X-ray is not a good technique to analyze paintings

E states that X-ray detects lead-based white pigments, but what if the underneath layers are not painted with lead-based paint? Clearly it weakens the argument!

E it is.

let's see how others do not weaken the argument:
(A) There is no written or anecdotal record that Leonardo da Vinci ever painted over major areas of his Mona Lisa.
so what? maybe no one knew about that? moreover, it rather strengthens the argument than weaken.

(B) Painters of da Vinci’s time commonly created images of mountainous scenery in the backgrounds of portraits like the Mona Lisa.
but that does not mean that da Vinci did the same...he's very well known for not BEING like everyone else!

(C) No one knows for certain what parts of the Mona Lisa may have been painted by da Vinci’s assistants rather than by da Vinci himself.
this one is out of scope - as it talks about possibility that Mona Lisa might have been painted by da Vinci's assistants - nothing relevant to our argument

(D) Infrared photography of the Mona Lisa has revealed no trace of hidden mountainous scenery.
Infrared testing is out of scope here.

Argument: X-ray analysis didn't find anything --> no hidden mountain.
Logic: X-ray analysis can measure everything.
Diagnosis: To break this argument we want to know if there is something that can go undetected by X-rays.
Solution: Option E -Analysis relying on X-rays only has the capacity to detect lead-based white pigments in layers of paint beneath a painting's surface layers - provides us with what we need i.e., the limitations of an X-ray analysis.

Premise: Using computer techniques, researchers analyze layers of paint that lie buried beneath the surface layers of old paintings.
Conclusion: Additional mountainous scenery once appeared in Leonardo da Vinci’s Mona Lisa, which was later painted over.
Objection (to conclusion) from Skeptics: That X-ray examinations of the Mona Lisa do not show hidden mountains.

Choose the option that weakens objection (does not necessarily mean choosing the option that strengthen the conclusion)

(A) There is no written or anecdotal record that Leonardo da Vinci ever painted over major areas of his Mona Lisa.
==>May or may not true. Also, records are Out of scope. <-----eliminate

(B) Painters of da Vinci’s time commonly created images of mountainous scenery in the backgrounds of portraits like the Mona Lisa.
==> May be true. But still does not provide solid evidence whether Da Vinci himself used to follow the practice. Moreover, even if he did, was MonaLisa not an exception? <-----eliminate

(C) No one knows for certain what parts of the Mona Lisa may have been painted by da Vinci’s assistants rather than by da Vinci himself.
==>Out of scope. question is about the use paint beneath the surface layer or about the mountainous scenery.<-----eliminate

(D) Infrared photography of the Mona Lisa has revealed no trace of hidden mountainous scenery.
==>May be true. But the question is was it there once? moreover, option doesn't claim that this technology itself is a fullproof method to conclude something.<-----eliminate

(E) Analysis relying on X-rays only has the capacity to detect lead-based white pigments in layers of paint beneath a painting’s surface layers.
==> May be true. Moreover since all other options have gone, this looks convincing.

Hope this helps.

Looks like many people think B also can be answer and few posts states B should be answer if E was not provided, My question is why B could be correct answer as painters of da Vinci's time "COMMONLY" created.... does not state Da Vinci to created that in and also "COMMONLY" give more reason to not select this option.­

Argument of Skeptics:

Premise: X-ray tests on painting didn't reveal any underlying painting
--->
Conclusion: There is no underlying painting.

Something that weakens the above conclusion is to prove that the premise is wrong. i.e, We can't rely on X-ray tests to conclude that.

Option E conveys the same.

Can the capacity written in option E be attributed to limited capacity??.

If I understand your question correctly, then yes! (E) states that "analysis relying on X-rays only has the capacity..."

Here's another example: "My car only has the power to go up to 100 mph." - My car has some power (a limited amount of power), but not enough power to go over 100 mph.

I hope that helps!

Straightforward Answer Choice E

Conclusion of skeptics: X-ray examinations of the Mona Lisa do not show hidden mountains.

We need to weaken the conclusion

From Option E we can deduce that X-rays in this case do something more than that what the skeptics believe

I picked B, but wasn't too happy about it. I have concluded that this is an example of a question where the weakener is not catastrophic for the argument, only mildly so.

Answer is E.

GMATNinja

I chose the correct answer for this question, but I think a lot of CR weaken questions have a trap answer like (B) and wanted to clarify why it's certainly incorrect: it's wrong because it doesn't attack the link between the relationship between X-Ray (premise) and whether there's are hidden mountains underneath the layers (conclusion)? I think there are a few questions with answers like (B) that claims it's common to do X, and therefore, the conclusion that goes against X is wrong - let me know if I'm missing something here. Thanks!

You're on the right track!

The key here is to look at the exact language of the question: "Which of the following, if true, would tend most to weaken the force of the skeptics’ objections?

Here, we're looking specifically for something that most weakens the force of the skeptics' argument. That argument relies on X-ray examinations. (E) deals a strong blow to the force of this particular argument. (B), on the other hand, offers very mild support that there may have been mountains, but does not weaken the force of the skeptics' specific objection.

I hope that helps!

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