When a new product is added to an existing line, what type of branding does it illustrate?

The situation described involves adding a new product to an existing line, which aligns with the concept of family branding. Family branding refers to the practice of marketing several related products under a single brand name, leveraging the established reputation and recognition of that brand. By introducing a new product within the existing line, the brand capitalizes on existing customer loyalty and brand awareness, which can facilitate consumer acceptance and reduce the risks associated with launching a new product.

In contrast, co-branding involves partnering with another brand to create a product that features elements of both brands, while brand extension refers to the application of an established brand to a new product category. Brand differentiation emphasizes distinguishing a brand from its competitors in the marketplace, which is not specifically what is illustrated by adding a new product to an existing line. Family branding, therefore, is the most correct interpretation for this scenario, as it specifically addresses the addition of a new product to a cohesive product family under one brand umbrella.