Final answer:
Salaries paid to its sales staff are considered a retail selling expense for a candle shop. These expenses are directly tied to the selling process, unlike interest on loans or office supplies.
Step-by-step explanation:
Out of the given options, salaries paid to its sales staff is a retail selling expense for a candle shop. Retail selling expenses are the costs directly associated with the sale of products. These include the wages or salaries of sales staff, commission on sales, rent for retail space, utilities for the store, and promotional materials directly tied to selling products. Interest payments on a start-up loan, while a financial expense for the business, are not tied directly to the selling process. Similarly, office supplies are considered general administrative expenses, and mall rent, although necessary to maintain a sales presence, is categorized more generally under occupancy costs rather than direct selling costs.