Final answer:
The job classes that are based on Dine-in guests only according to the FY19 updated Labor Matrix include A. Server and B. Food Runner, as well as C. SA and D. Bar staff, who serve dine-in customers directly.
Step-by-step explanation:
In a restaurant setting, different job classes cater to various aspects of the dining experience. Considering the FY19 updated Labor Matrix, the job classes that are based exclusively on Dine-in guests are typically those that directly interact with customers dining in the establishment. These would include A. Server, whose primary role is to take orders and serve food and drinks to guests seated at tables, and B. Food Runner, who assists in bringing food from the kitchen to the guests' tables. The role of C. SA, also known as Service Assistant or Busser, involves cleaning and setting tables, which is also directly linked to dine-in services. Position D. Bar staff, which includes bartenders and bar assistants, serve beverages to dine-in customers, either at the bar or to be delivered to their table by the server. In contrast, roles such as E. To Go Server, focus on customers who are picking up food to eat elsewhere, and thus, are not part of the dine-in centric job classification.