Answer:
This is an example of anticipating.
Explanation:
Barriers to effective listening often prevent an individual from being able to consciously and actively listen and understand what is being said.
In this case, Sam's barrier is anticipating. Anticipating is a form of prediction, of expecting something. In this case, Sam has already heard a speech about vegetarianism and thus thinks she already knows what Gustavo is going to say.
She is anticipating and therefore believes it is no longer necessary or important to pay attention, thus creating a barrier to her listening.
