Dante is healthier than his twin brother because he developed with a better placental barrier against viruses. this best illustrates the impact of on development.

Prenatal environment

Explanation:

Prenatal environment  is defined as the surrounding of the uterus were the unborn child is present before birth.This environment establishes the link between unborn child and the mother through the placenta. It helps in improving the development of child and preserving fetus from virus and other hazards  

According to the questions situation, the scenario is depicting about the development based on prenatal environment.Due to this factor, Dante is more healthier as compared to is twin brother because he was preserved from viruses in prenatal environment and his brother got affected with viruses comparatively .

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