Research Demonstrates That When Black and White Students Are Reminded

Research demonstrates that when Black and White students are reminded of their race (or not) before taking a test, Black students show lowered performance in the condition where they are reminded of their race. This result is MOST accurately interpreted as:

A) an effect of race on test performance.
B) an effect of the extent to which people are thinking about their race on test performance.
C) an interaction between race and the extent to which people are thinking about their race before a test.
D) a correlation between racial identity and the extent to which one is thinking about their race prior to a test.