Refer to the input text as context and select the correct relationship between 'Amazon Prime' and 'Amazon' from the available options.
Options: brand, stock exchange, chief executive officer, owned by

The world’s largest bricks-and-mortar retailer has taken aim at e-commerce giant Amazon.com Inc. recently, by rolling out an unlimited shipping service for $50 a year , which is about half what Amazon charges for its Amazon Prime service.
owned by