Final answer:
The Russian service is most commonly used for large groups.
Step-by-step explanation:
The correct answer is B. Russian.
The Russian service is most commonly used for large groups, as it typically involves several courses served in a specific order.
It is characterized by multiple dishes being served all at once, allowing guests to help themselves to the various items on the table.
This type of service is commonly seen in Russian cuisine and is often associated with banquets, celebrations, and formal events.