Twin studies and studies of adopted children allow behavioral geneticists to research the
a) polygenic nature of inheritance.
b) relative contributions of genes and environment.
c) ways genes always win over environment.
d) ways environment always wins over genes.

Option-B

Explanation:

Behavioural genetics is the field of study in which the geneticists study the contribution of the genes and the environment on the behaviour of the person.

To study such effects the behavioural genetics conduct their studies on the twin children which share parents and the environment and the adopted children's which have the different genes but share the same environment as of the parents after adoption. This allows to compare and study the contribution of the genes and the environment on the behaviour.

Thus, Option-B is the correct answer.

the endomembrane system i think