Reported racial gaps in average intelligence scores are most likely attributable to

A) the use of biased tests of intelligence.
B) the use of unreliable tests of intelligence.
C) genetic factors.
D) environmental factors.

Numerous studies have suggested that racial gaps in average intelligence scores are largely due to environmental factors, such as differences in access to quality education, nutrition, and exposure to toxins. It is important to note that these environmental factors are often linked to race due to historical and social inequalities, but they are not inherently tied to genetics or inherent differences in intelligence between different racial groups. Therefore, option D is the best answer. Options A and B are less likely because reputable tests of intelligence are generally designed to be fair and reliable across different groups, and flaws in testing methods are not likely to consistently produce racial gaps in test scores. While genetic factors may play some role in individual differences in intelligence, they are not likely to account for large differences in average intelligence scores between different racial groups.