A. United States is not correct.

Among the United States' young adults (that is, the population aged 25-34), 41% are college graduates. While this is only slightly above the OECD average of 37%, it is also equal to the proportion of Americans aged 55-64 who have completed college.

In other words, Americans have not made any progress in their level of educational achievement over the past three decades, as measured by college graduates. This stands in sharp contrast to the increase most other advanced countries have experienced.

The stagnation is partly due to the increasing cost of a college education in the United States. Students at four-year public colleges paid an average of $8,244 for in-state tuition and fees in 2011 — a 8.3% jump that was more than twice the overall rate of inflation, according to the College Board. Average private college tuition increased by 4.5%, to $28,500, in 2011. With average inflation-adjusted household incomes falling during the preceding decade, higher tuition has made college far less affordable for many families.

B. France is not correct.

The proportion of college graduates in France has risen remarkably — from 18% in the 1970s, which was when today's 55-64 year olds graduated, to 43% among today's 25-34 year olds. Unlike their parents' generation, young French employees are thus considerably more likely to be college graduates than are young American workers.

In comparison, in Europe's largest economy, Germany, only about a quarter of both younger and older adults have completed advanced education. However, as the example of Germany shows, having a relatively low percentage of university graduates does not necessarily mean that an economy is uncompetitive, or that young people who lack college degrees face lower wages or a higher prospect of unemployment. A well-diversified job training system also plays a significant role.

C. South Korea is correct.

The advance in the level of educational achievement in South Korea over the last few decades is nothing short of astonishing. While only 13% of those aged between 55 and 64 years have completed college, an astounding 63% of Koreans aged 25-34 are college graduates.

In comparison, the share of young adults who have graduated from college stands at 6% in China, 12% in Brazil and 55% in Russia.

D. Canada is not correct.

In Canada, 56% of young adults have attained a college education, tying with Japan for second place aomng OECD countries. In comparison, 41% of older Canadians (aged 55-64) have completed college. Thus, in contrast to the United States, Canada has continued to expand access to higher education in recent decades.