Premise: The Duke and Duchess of Sussex have touched down in Sydney ahead of their first official trip to Australia as a couple. Prince Harry and Meghan will begin their official duties tomorrow with a visit to Sydney Harbour, Admiralty House, and Taronga Zoo. The tour coincides with the Invictus Games, the sporting event founded by Prince Harry which gives injured service personnel and veterans a chance to compete in a variety of sports. The event is expect to attract more than 100,000 people.
Hypothesis: A Duke holds the highest hereditary title.