Final answer:
Genetics has the greatest impact on how people obtain their gender identity.
Step-by-step explanation:
The greatest impact on how people obtain their gender identity is genetics. Each person inherits a set of genes that determines their biological sex, including their sex chromosomes (XX for females and XY for males). These genes influence the development of reproductive organs and secondary sexual characteristics. While other factors such as nutrition, body type, and social influences may play a role in shaping gender identity, genetics is the primary determinant.
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