Although the ratio of physicians to total population is

I agree with A.

The statement states that because there are 33% more surgeons in the US there are more operations there. This means that there cannot be any other reason for greater number of operations, which is possible only if A is assumed.

If A were not true, then there is 40% more operations in the US not because of more surgeons, but because of more people needing them.

The original sentence says More Surgeon means more surgeries
A eliminates another explanation. So A in a way tries to strengthen. So A is a assumption.

Further if we try to negate option (A) it will be -

Patients in the United States have a greater need for surgery than do patients in Canada.

This clearly attacks the conclusion , which states -



Thus answer will be (A)

Hi,

Let us analyze the conclusion and the premise on which it is based:

Conclusion: Clearly, this is the reason people in the United States undergo 40 percent more operations per capita than do Canadians.

Premise: The United States has 33 percent more surgeons per capita.

ie; the fact that the US has more surgeons per capita is the causal factor behind US citizens undergoing 40% more surgeries per capita. In order to identify an underlying assumption, we need to rule out any one of:

a) An alternative explanation
b) Reverse causality
c) A correlative factor

Option (A) states: patients in the United States do not have a greater need for surgery than do patients in Canada.

This is ruling out an alternative explanation/reason for US citizens undergoing 40% more surgeries per capita. Hence, this is the correct answer option.

Hope this clarifies.

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Although the ratio of physicians to total population is about the same in the United States and Canada, the United States has 33 percent more surgeons per capita. Clearly, this is the reason people in the United States undergo 40 percent more operations per capita than do Canadians.

The explanation given above rests on an assumption that:

(A) patients in the United States do not have a greater need for surgery than do patients in Canada.
(B) the population of the United States is not larger than that of Canada.
(C) United States patients sometimes travel to Canada for certain kinds of surgery.
(D) General practitioners in the United States do not as a rule examine a who is a candidate for surgery before sending the patient to a surgeon.
(E) There are no unnecessary surgical operations performed in Canada.
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Here is an explanation, which may help you.
1. per capita surgeons --> for 1000 people, how many surgeons (it could be 100 people or 10000 people)
Assume (for the explanation purpose) in Canada, for 1000 people, 10 surgeons. So, in US, for 1000 people, 14 surgeons (33% more surgeons, rounded to 40%)

2. The conclusion of the argument is: Since per capita surgeons are more in US than in Canada, more surgeries (40% more operations) are happening in US. In my opinion these % numbers are not that important for the argument's conclusion. This conclusion is directly connecting per capita surgeons to the number of operations. If we bring in any new information that would make us believe that, yes more surgeons means more operations, then that choice is the 'assumption'.

A) if patients in US need more surgeries than do patients in Canada, then the total number of surgeries in US will be more than surgeries in Canada, so we can't directly correlate 'more surgeons to more surgeries'. If this is the case, then the conclusion is invalid. Correct answer

I chose B, can someone explain this with an example by assuming numbers? Thanks in advance

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