The event which is most likely occurring in this scenario is effusion because there is a movement of a gas through a small opening into a larger volume and is denoted as option C.
<h3>What is Effusion?</h3>
This is referred to as the process in which a gas or a substance escapes from a container through a hole of diameter which is usually smaller.
The type of event which is most likely occurring is effusion because of the presence of the small holes in which the balls are made to pass through the center which is why option C was chosen.