please answer questions

QUESTION 10 Studies on the effect of the race of the tester have demonstrated that O a. White children consistently score higher when they are tested by White examiners. O b. African-American children consistently score higher when they are tested by African-American examiners. O c. the race of the examiner does not have a consistent effect on the test scores of African-American or White children. O d. African-American children consistently score lower when they are tested by African-American examiners