A career in dermatology is still a safe bet for medical school graduat

Question

A career in dermatology is still a safe bet for medical school graduates. In the U.S., the number of cases of skin cancer linked to ultraviolet (UV) radiation in sunlight has remained relatively constant every year even though far fewer adults are intentionally exposing themselves to UV sunlight now than were doing so at the height of the suntan craze 20 years ago.

Each of the following, if true, could explain the relative stability in the incidence of skin cancer each year despite the decrease in intentional exposure to UV sunlight EXCEPT:

(A) Because of decreasing levels of ozone in the upper atmosphere, more people are now exposed accidentally to excessive UV sunlight.

(B) People who continue to intentionally expose themselves to UV sunlight are absorbing larger doses of the harmful radiation than the average sun-tanner did in the past.

(C) Levels of UV radiation from sources other than sunlight are increasing every year.

(D) While fewer women are intentionally exposing themselves to UV sunlight, the number of men doing so has increased significantly.

(E) In most victims, skin cancer is linked to exposures to UV sunlight that occurred up to 30 years before the onset of the disease.

Can someone explain why B is wrong?
My logic is, 
Say 
earlier there were 
Total number of people = 100 ( 60 intentionally exposing +40 other reasons ).

Now 
Total number of people =100 ( 20 intentionally exposing +80 other reasons )

So ,now these 20 people can expose as much they can, but they cannot effect the total number. 
Atleast they can not increase the total number.
So, Why B is wrong, when it is giving us information about intensity of exposure.
And cancer rate is no where in ques. Argument is only about total number of cases.

KarishmaB · Accepted Answer

If I were to just skim through the options and option D was not there, I might think that B is correct too. But on further analysis, you find that D is the correct answer. Let's see why.

Argument: 
- the number of cases of skin cancer linked to UV radiation in sunlight has remained relatively constant
- far fewer adults are intentionally exposing themselves to UV sunlight now

This is a paradox, right? How will you explain it? By saying that either 
1. people getting exposed unintentionally is increasing or 
2. the incidence of cancer among people getting intentionally exposed is increasing (I will explain what this means soon)

Options A and C basically give you the reason 1 above.

Option B gives you the reason 2 above. 
Say, out of 100 total people, 40 were intentionally exposing themselves to UV rays. Incidence of cancer among these 40 was 10% i.e. 4 of them used to get afflicted by cancer.
Now, say only 20 intentionally expose themselves but take much higher doses. Say now the incidence of cancer among them is 25% (increased because of higher dose). Again 4 people will get afflicted. 
So B can also explain the paradox.

But D cannot. Proportion of men and women is immaterial. The overall number of people exposing themselves to UV rays intentionally has certainly decreased as given in the argument.

chetan2u · Answer

A career in dermatology is still a safe bet for medical school graduates. In the U.S., the number of cases of skin cancer linked to ultraviolet (UV) radiation in sunlight has remained relatively constant every year even though far fewer adults are intentionally exposing themselves to UV sunlight now than were doing so at the height of the suntan craze 20 years ago.

Each of the following, if true, could explain the relative stability in the incidence of skin cancer each year despite the decrease in intentional exposure to UV sunlight EXCEPT:

(A) Because of decreasing levels of ozone in the upper atmosphere, more people are now exposed accidentally to excessive UV sunlight.
 So more people are getting exposed accidentally...does explain

(B) People who continue to intentionally expose themselves to UV sunlight are absorbing larger doses of the harmful radiation than the average sun-tanner did in the past.
 Now the exposure has increased, so incidence of cancer has remained relatively constant....... A close second to choice D

(C) Levels of UV radiation from sources other than sunlight are increasing every year.
  clearly explains

(D) While fewer women are intentionally exposing themselves to UV sunlight, the number of men doing so has increased significantly.
 women may have stopped and more men may have increased but overall we know the exposure by adults has decreased. Doesn't matter what constitutes the adults who are exposing themselves but the number has decreased... Doesn't explain

(E) In most victims, skin cancer is linked to exposures to UV sunlight that occurred up to 30 years before the onset of the disease.
 again explains. The present cases are related to time when exposure was more

D

ronr34 · Answer

Hi Karishma,
Don't you find it that option D is actually negating the statements?
If it's stated that far less adults are exposing themselves intentionally, than what does it matter if more men are exposing while the number of women is decreasing? 
Either way, the total number is decreasing...
No?

KarishmaB · Answer

You are correct but that is the point - it is an EXCEPT question: 
"... could explain the relative stability in the incidence of skin cancer despite the decrease in intentional exposure EXCEPT"
So (D) does not explain the stability in the incidence. It doesn't matter whether number of men is increasing or number of women is decreasing. The point is that total number is decreasing. So it doesn't explain the stability in the incidence of skin cancer.

StudiosTom · Answer

Given: 1.Number of cases of skin cancer linked to UV radiation in sunlight has remained relatively constant every year 
2.Far fewer adults are intentionally exposing themselves to UV sunlight now than were doing so at the height of the suntan craze 20 years ago.

Type of question: EXCEPT

Reasoning:Correct me if i am wrong,
(A) Because of decreasing levels of ozone in the upper atmosphere, more people are now exposed accidentally to excessive UV sunlight- explains the cause of cancer.Even though few adults are intentionally exposing,but due to reason specified they are exposed accidentaly.So it explains.Eliminate.

(B) People who continue to intentionally expose themselves to UV sunlight are absorbing larger doses of the harmful radiation than the average sun-tanner did in the past-Correct

(C) Levels of UV radiation from sources other than sunlight are increasing every year.-Other source of radiation ,here alternative cause explained ,so eliminate

(D) While fewer women are intentionally exposing themselves to UV sunlight, the number of men doing so has increased significantly- Irreleveant as not about male/female but about adults

(E) In most victims, skin cancer is linked to exposures to UV sunlight that occurred up to 30 years before the onset of the disease.-Since cancer caused due to time older than 30 years,it explains the cause.

arvind910619 · Answer

Imo D 
This is an except question and we have to be careful that we keep that in mind.

A this actually helps to explain the relative stability of skin cancer among folks.

B This helps that people mistakenly are receiving more doses of UV radiating leading to skin cancer. Thus this choice also helps to explain the stability.

C Again if this the case then more people will be exposed to more UV radiation and they might not know the source.

D Correct. While this choice breaks up the population in gender, still this does not explain stability in the skin cancer. More men are exposing themselves than women this can lead to various cases and we do not know the number of female or female to ascertain the overall impact of such trend. This is our answer.

E This choice also explains the stability of the cancer.

JS1290 · Answer

Hi  VeritasKarishma ,

I am confused with option C as to why it can't be the answer. In the argument we are specifically given that "the number of cases of skin cancer l inked to ultraviolet (UV) radiation in sunlight  has remained relatively constant every year". If we are strictly talking about  UV radiation in the sunlight , sources other than the UV radiation are completely irrelevant to the argument, aren't they? Could you please comment on this?

KarishmaB · Answer

Hey csaluja,

I am totally with you on that one. The argument does say "UV radiation in sunlight". But here is the thing - the only source of UV radiation has been sunlight. But now other sources are increasing. Now since we are talking about a career in dermatology, the number of cases of skin cancer due to UV radiation from any source is the same. 
Strictly speaking, you are right. But since option (D) is worse and we get what the argument and option (C) intended to say, we let it slide here. In an official question, they would talk about "skin cancer due to UV radiation" and not "skin cancer due to UV radiation in sunlight".

berdibekov · Answer

I don't agree with you on this one. 
The passage talks about  adults : 
In D, while fewer women are intentionally exposing themselves to UV sunlight,the number of men doing so has increased significantly - how do we know that men does not include children? 
So, I think this is not a quality question and should be not considered for study.

Bunuel · Answer

KAPLAN OFFICIAL EXPLANATION

Here's another question that touches on a whole bunch of the logical elements we've been discussing. We're asked to find the choice that could not possibly explain a phenomenon. This tells us that four of the answer choices could possibly explain the paradoxical phenomenon. As always, read the stimulus carefully, paying close attention to the details and what they imply. Here's the story: Since far fewer adults are intentionally exposing themselves to UV sunlight today compared to 20 years ago, the number of cases of skin cancer linked to exposure to the UV radiation in sunlight should be decreasing. But the passage creates a seeming paradox, because the number of cases of skin cancer has actually remained constant every year. Four of the answer choices will resolve the paradox by providing alternative explanations for the phenomenon of skin cancer that are not related to the total number of adults today who are intentionally exposing themselves to sunlight. The correct answer will leave the paradox intact.

An 800 test taker has a sense for what the right and wrong choices will look like or do, even when, in an "odd-man-out" situation, she can't pre-phrase such choices precisely.

(D) is the one that does not help to resolve the paradox. Even if the number of men who are intentionally exposing themselves to UV sunlight has increased, we still know from the stimulus that far fewer adults altogether are intentionally exposing themselves. So the mystery remains: the rate of skin cancer among adults altogether should be decreasing, although we're told it's not.  (D) is the answer.  The other four choices, however, do provide acceptable solutions to the mystery:

(A) Accidental exposure to UV sunlight may be compensating for the decrease in intentional exposure, keeping the cancer rate the same.

(B) The cancer rate among people who intentionally expose themselves to UV sunlight may be higher because they are getting a larger dose of the harmful rays, thus keeping the overall cancer rate the same.

(C) If levels of UV radiation from sources other than sunlight are increasing, that could compensate for the decrease in intentional exposure to the sun.

(E) If skin cancer is linked to exposures to sunlight that occurred up to 30 years before the onset of the disease, then the decrease in intentional exposure to UV sunlight in recent years probably does not yet show up in the rate of skin cancer.

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A career in dermatology is still a safe bet for medical school graduat

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