Which of the following companies is NOT a key player in the cruise industry?

Hilton is not a key player in the cruise industry because it primarily operates within the hotel and resort sector. While Hilton is a prominent name in hospitality, focusing on accommodations and related services, it does not engage in cruise line operations. The other companies listed—Carnival, Royal Caribbean, and Norwegian—are major cruise lines that offer a variety of itineraries and experiences on the water. They are recognized for their extensive fleets and significant contributions to the cruise tourism market, but Hilton's business model revolves around land-based hospitality rather than maritime travel. This distinction clarifies why Hilton is not considered a contender in the cruise industry context.