Critical Reasoning

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.

OA D

i chose D because I was thikning that this would show an increase in the incidences instead of staying the same

why not B?

tough call between B and D. I choose D but dont know why cant it be B

D if true explains the paradox.

Fewer women exposing themselves to UV is counteracted by an increase in the number of men exposing themselves to UV and thus the relative stability in the incidence of skin cancer is maintained.

But B doesn't do so.

IMO B.

Why not ' A' ?

Though I opted for B, on further analysis I feel D is correct.

My Reasoning:

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: (note the bold words)

(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. (since people are absorbing higher doses of UV...means higher incidence of disease...so supports the argument)
(D) While fewer women are intentionally exposing themselves to UV sunlight, the number of men doing so has increased significantly. (in this case, the overall intentional exposure remain either constant or increase...in both case it violates the agrument...so correct choice)

Sorry for re-opening the topic. Doesn't B mean that number of people are still the same, only the exposure to levels of UV sunlight has increased? In D, less number of women and more number of men may or may not maintain the same number of people exposed to UV sunlight.

Hi,

agatsya wrote:Sorry for re-opening the topic. Doesn't B mean that number of people are still the same, only the exposure to levels of UV sunlight has increased? In D, less number of women and more number of men may or may not maintain the same number of people exposed to UV sunlight.

B) Note that the stimulus does not state that intentional exposure by itself causes skin cancer. In other words, one can moderately expose himself to sunlight and not get skin cancer. However, since B states that 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, there are chances that the number of cases of skin cancer from this category would have gone up (more exposure). Hence B could explain the stability in the incidences of skin cancer even though far fewer adults are intentionally exposing themselves to UV sunlight now.

D) Since the stimulus states that total number of adults intentionally exposing themselves to UV sunlight is lower than what is was 20 years ago, the change in the number of women v/s men in the overall number of adults does not give any additional information and hence is the helpful in explaining why the TOTAL number of cases of incidence of skin cancer are stable despite the decrease in intentional exposure.

Hope this helps.

T11

T11 wrote:Hi,

agatsya wrote:Sorry for re-opening the topic. Doesn't B mean that number of people are still the same, only the exposure to levels of UV sunlight has increased? In D, less number of women and more number of men may or may not maintain the same number of people exposed to UV sunlight.

B) Note that the stimulus does not state that intentional exposure by itself causes skin cancer. In other words, one can moderately expose himself to sunlight and not get skin cancer. However, since B states that 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, there are chances that the number of cases of skin cancer from this category would have gone up (more exposure). Hence B could explain the stability in the incidences of skin cancer even though far fewer adults are intentionally exposing themselves to UV sunlight now.

D) Since the stimulus states that total number of adults intentionally exposing themselves to UV sunlight is lower than what is was 20 years ago, the change in the number of women v/s men in the overall number of adults does not give any additional information and hence is the helpful in explaining why the TOTAL number of cases of incidence of skin cancer are stable despite the decrease in intentional exposure.

Hope this helps.

T11

@T11 - The assumption " In other words, one can moderately expose himself to sunlight and not get skin cancer." cannot be deduced from the passage.

Remember, our job is to identify the one statement that could not explain the relative stability in spite of the sharp decline in the number of people who intentionally expose themselves. Such a statement will either be clearly irrelevant or serve only to make the paradox more mystifying or require dubious assumptions.


(D) The gender of the people who do so is not relevant, since it was made clear that the number of people who expose themselves intentionally has dropped. (B) forms the basis for a possible explanation: the fewer people who do expose themselves on purpose are getting larger doses of UV, so it may well be that any decrease that might be caused by a decline in the number of people exposing themselves to UV is offset by greater prevalence of cancer among those that do expose themselves. If radiation is harmful, it stands to reason that a lot of radiation may be very harmful

I did this question today again and convinced with D. B tells you why the number of people are constant. It is because people absorbing more UV radiations.

Looks like an old topic : But I find "C" also doesn't help explaining the paradox. the observation was about cancer linked to sunlight. can someone explain why C is wrong? I agree with D - but unable to eliminate C.

pnk wrote:Though I opted for B, on further analysis I feel D is correct.

My Reasoning:

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: (note the bold words)

(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. (since people are absorbing higher doses of UV...means higher incidence of disease...so supports the argument)
(D) While fewer women are intentionally exposing themselves to UV sunlight, the number of men doing so has increased significantly. (in this case, the overall intentional exposure remain either constant or increase...in both case it violates the agrument...so correct choice)

Your reasoning about B is very clear, but according to your reasoning for choice D consider this please

the number of women who intentionally expose themselves in the past was :20
the number of men who intentionally expose themselves in the past was :17

Now, the number of women who intentionally expose themselves is :15
the number of men who intentionally expose themselves is :21

Thus, the overall number of people is decreasing (37 vs. 36) which is able to violates the argument