To display only the proper lead sources based on the product category chosen, an administrator should create a dependency between the Product Category field and Lead Source field on Lead object. A dependency is a relationship between two picklist fields that restricts the values available in one picklist based on the value selected in another picklist. For example, an administrator can create a dependency that shows only Online Store and Social Media as lead sources if Product Category is Shoes, but shows only Trade Show and Magazine as lead sources if Product Category is Apparel. Creating a page layout for each category, creating business processes and record types for each category, or creating a single business process with record types for each category will not display only the proper lead sources based on the product category chosen. Reference: https://help.salesforce.com/s/articleView?id=sf.customize_dependent.htm&type=5