Final answer:
Chairs are often not pushed in at dining settings to provide option (c) easy access for guests, serving as a practical and inviting arrangement.
Step-by-step explanation:
In setting the dining room, chairs are often not pushed all the way in for easy access option (c). This arrangement allows guests to easily move the chairs and take their seats at the table. It's also typically done to create a more welcoming and inviting environment, signaling to the guests that they are expected and the space is prepared for them. While aesthetic preference and creating a casual atmosphere might also be considerations in some contexts, easy access remains a practical reason for this common practice.