IMO D.

Only D tells us that how the following statement was not correct: "Some political commentators and economic historians contend that President Franklin Roosevelt's New Deal single handedly propelled the United States out of the Great Depression and into decades of uninterrupted prosperity"

I think B could be an effect of the New Deal. So I turn it out and pick D.

(D) most weaken the argument attacking the fundamental premise of "these economists"

OA?

OA:
The argument's claim is: the "New Deal singlehandedly propelled the United States out of the Great Depression and into decades of uninterrupted prosperity."

The argument's evidence for this is: "during the years following 1933, GDP grew, unemployment shrunk, and optimism increased."
There are two major ways to undermine the claim that the "New Deal singlehandedly propelled the United States out of the Great Depression and into decades of uninterrupted prosperity." (1) Show that another event propelled the United States out of the depression. (2) Show that the New Deal did not propel the Unites States out of the depression.

In order to weaken the argument, it would be helpful to weaken the evidence cited in the argument ("economists note that during the years following 1933, GDP grew, unemployment shrunk, and optimism increased").

Most of you have it right. Thanks!

Option D offers the strongest challenge to the author's argument.
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Conclusion: New Deal single handedly propelled the United States out of the Great Depression and into decades of uninterrupted prosperity.

B isn't an alternative cause.
New Deal began in 1933 and years following 1933 saw increase in GDP, employment and optimism. In 1941, after US was out of the Great Depression, there could have been an additional cause of these increases. New Deal could have still single handedly propelled US out of the Great Depression. Hence B doesn't weaken the conclusion.


D weakens the conclusion by saying that the prosperity was not uninterrupted - no matter how long the interruption was.
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The argument says that the New Deal single handedly pulled the country out of depression, not that it alone was responsible for decades of uninterrupted prosperity. Since the time gap between 1933 - when the deal began- and 1941 - when US entered World War II- was quite large (of about 8 yrs), it is still possible that the New Deal single handedly pulled US out of depression in mid and late 30s and the World War provided a further boost to the economy later (after US was already out of depression). Hence B doesn't necessarily weaken the conclusion.
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6. The New Deal in America began in 1933 and included widespread bank reforms, unprecedented government infrastructure spending, and unparalleled expansion in the size of government. Some political commentators and economic historians contend that President Franklin Roosevelt's New Deal singlehandedly propelled the United States out of the Great Depression and into decades of uninterrupted prosperity. To support this claim, these economists note that during the years following 1933, GDP grew, unemployment shrunk, and optimism increased.

Which of the following statements, if true, would most weaken the above argument?

A) The considerable debt burden that the government assumed to fund the New Deal sparked fear in the minds of some economists, investors, and businessmen.
B) The considerable government expenditures and massive labor requirements engendered by America's entry into World War II in late 1941 helped employ Americans and grow GDP.
C) On average, GDP per capita fell and unemployment rose in many foreign countries during the years after President Roosevelt announced his New Deal.
D) During 1939, the U.S. economy contracted sharply, unemployment jumped 5%, and America's optimism fell.
E) U.S. GDP during the mid 1930s stood at levels much lower than 30 years later.

why not b?
if there were another reason for the decreased unemployment rate and increased GDP, the argument could be weakened.
And i think that b can be another reason.

IMO D.

Choice B talks about other possible causes that could have propelled America into years of uninterrupted prosperity. However, the year that option B mentions is 1941. The New Deal was already put into action by 1933. That is why its positive effects were observed after 1933. So a cause in 1941 could not have been responsible for the positive effects observed after 1933.

Option D directly negates the main premise that the economists supporting the New Deal state. By introducing this contrasting evidence, it reduces the likelihood of the conclusion that the years following 1933 were all positive. Had all the years been positive, 1939 would not have seen this decrease.

That is why option D weakens the argument. Hope this explanations helps.
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