What are the [politically correct] reasons for test score gaps?

from: http://thenotebook.org/articles/2015/11/24/how-race-and-class-relate-to-standardized-tests

What are the reasons for these gaps?

Many researchers say that an “opportunity gap” leads to an “achievement gap.” Socio-economic factors including income levels, educational attainment, employment rates, housing options, neighborhood crime rates, and resources available to schools, are worse for African Americans and Hispanics, on average, than for Whites. These circumstances often lead to fewer opportunities for African American and Hispanic children to access a wide range of activities and experience an enriched educational environment from birth onward.

African Americans and Hispanics often do not have the educational advantages that more wealth brings. More White students than Blacks and Hispanics have parents who went to college – the mother’s education level is a major test score predictor. For tests like the SAT, affluent students can pay for private coaching.

Many Hispanic children live in households where English is not the first language, sometimes giving them access to fewer educational resources.

As for the higher scores, on average, by Asians, a recent study concluded that “Asian and Asian American youth are harder working because of cultural beliefs that emphasize the strong connection between effort and achievement. Studies show that Asian and Asian American students tend to view cognitive abilities as qualities that can be developed through effort,” rather than being inborn.

[Obviously white and black beliefs about effort and achievement must be the same, only Asians are different.]