Which of the following traits is NOT determined by inheritance alone?

Intelligence is the trait that is most notably influenced by a combination of genetic inheritance and environmental factors. While there are genetic components that can affect cognitive abilities, environmental influences such as education, socio-economic status, nutrition, and life experiences play a significant role in shaping intelligence. This interplay means that intelligence cannot be attributed solely to genetic inheritance.

In contrast, traits like eye color, hair color, and eye shape are largely determined by genetic factors, specifically the combinations of alleles inherited from parents. Genetic inheritance plays a primary role in how these physical characteristics manifest, making them less influenced by environmental factors compared to intelligence.