Jamal was born with genes to be a professional athlete, but his environmental experiences never supported the development of his potential athletic ability, so he never became a professional athlete. This example illustrates the concept of a trait being:.

This example illustrates the concept of a trait being multifactorial.

Explanation:

Saying that a trait is multifactorial means that such trait depends on multiple genes as well as multiple environmental factors that influence them. According to the passage, Jamal does have the genes to be a professional athlete. Yet, since his environmental conditions have never been favorable, he did not become one. Simply having the "right" genes was not enough; there were other factors in place as well. Therefore, this is an example of a trait being multifactorial.

i believe the answer is:   psychological  experiment

in this experiment, wilhelm wundt became the first person that implement scientific method in analyzing the pyschological phenomenon.

due to this result, wilhelm wundt also able to make psychology to be acknowledged as a separate scientific field from biology.