Final answer:
An online retailer is a retail company. Amazon is a prime example, starting as an online bookstore and growing into a vast retail presence with both online and physical stores. Therefore correct option is C
Step-by-step explanation:
An online retailer is an example of a retail company. Retail companies are those that sell goods or merchandise directly to consumers. Amazon, for instance, is a well-known example of an online retail company which started by selling books online without a physical retail location and now sells a wide variety of products. Amazon's business model shows the use of economies of scale, utilizing large warehouses and advanced technology to keep costs low and efficiency high. This has allowed Amazon to become a dominant player in the retail industry, both online and with its expanding number of physical 'brick and mortar' stores.