What is Arthur Jensen known for in the field of psychology?

Arthur Jensen is primarily known for his contributions to the study of intelligence and its heritability, which fits under the umbrella of behavioral genetics. His work focused on the genetic and environmental influences on intelligence, particularly emphasizing the role of genetics in explaining differences in intelligence among individuals and groups. Jensen's most notable assertion was that a significant portion of the variance in IQ scores could be attributed to genetic factors, and he was an advocate for the idea that intelligence, as measured by IQ tests, is largely inherited.

In the context of this question, while Jensen may intersect with psychometrics, cognitive development, and intelligence testing, his groundbreaking and most controversial impact lies specifically within the field of behavioral genetics. His views sparked considerable debate and further research, influencing discussions about nature versus nurture and the implications of heredity for intelligence.

This focus on the genetic basis of intelligence distinguishes his contributions, making "C. His contributions to behavioral genetics" the most accurate choice.