Which of These Facts Supports the Idea That Racial Differences

Multiple Choice

Which of these facts supports the idea that racial differences in testing are driven by social environment and expectations?

A) The difference in GRE scores between "black" and "white" students disappeared after President Obama's election.
B) "Asians" have a mean IQ score about 15 points above that of "whites."
C) The same individual taking the same test could achieve very different scores based on how rested they were, the breakfast they had that day, or their stress levels.
D) IQ tests measure predicted scholastic achievement more accurately than they measure intelligence.