Final answer:
Differentiated products that offer a wide variety, are not available from competitors, and are highly customized may be difficult and costly for competitors to imitate.
Step-by-step explanation:
Differentiated products are distinct from their competitors in various ways such as physical aspects, location, intangible factors and consumer perception. These products can be difficult and costly to imitate for competitors, especially if they have a unique product mix or offer a wide variety of products, products that are not available from competitors, or highly customized products.