Helena is trying to make the point that extroversion, or sociability is not biologically determined. She uses the evidence that children whose biological parents are introverted, when adopted by extroverted parents, tend to be more sociable than children of introverted parents who are not adopted.
Jay then states that Helena is wrong because some of these children that Helena mentioned remain introverted no matter how young they are when adopted.
So, Helena is trying say that extroversion is not 100% set by biology and gives examples of why she believes this. Jay then tries to refute her by giving examples of some cases where biology still affected the sociability of children.
The issue is that Helena never stated that she thinks biology has no effect on extroversion in children. She merely states that biology is not the full determinant of extroversion, i.e. "extroversion, or sociability, is not biologically determined." This still allows for extroversion to be affected by some biological factors, it's just not completely biological factors that determine it.
This is exactly what answer choice (D) is saying: "biological factors do not play any role in a child being extroverted."
Hope that clears things up! Please let us know if you have any other questions.
Julie-VAugust 19, 2019
In order to see that Helena wasn't saying that extroversion is not 100% biologically determined, would we focus more on "tend to" in the second sentence? I thought answer choice (D) was referring to the first sentence of her statement. Thanks in advance for any clarifications!
