Answer:
The cocktail party effect
Step-by-step explanation:
The cocktail party effect is observed in the brain's ability to drive out all other noise, and focus one's auditory attention on a particular stimulus
This is sort of selective attention in the brain. It is analogous to when one is in a party and is able to focus on a single conversation amid the noise from the music and people. The brain decides which stimuli is most important to it and then reacts to it.