Final answer:
A section sign is used to determine where products are placed within the aisles of a retail store, providing guidance for precise shelving placement.
Step-by-step explanation:
In the context of product placement in a retail environment, the correct locator sign for determining where products go in the aisle is the section sign. A departmental sign indicates a larger area of the store dedicated to a general category of products, like 'Electronics' or 'Apparel'. A category sign often refers to a subset within the department, such as 'Laptops' within the 'Electronics' department. The subsection sign, if used, would further divide the category into even more specific groupings. However, when specifically assigning products to particular locations within aisles, the section sign is utilized to guide the precise shelving placement.