Answer:
b) The competitive advantage White Castle achieved from being first was not sustainable.
Step-by-step explanation:
It is evident that White Castle was the first to open such a store. However, non-technological innovations are not sustainable in the long run, as they usually cannot be patented or protected from competition.
When competitors (McDonalds) followed the same or similar business model, they have advanced and incorporated new competitive advantages that defined the new market leader. Sticking with the advantage from being first does not guarantee long-term success, as it is always possible to become overridden by competition and their takes on the initial innovation or business model.