Please answer the following question: Information: - Gold, commonly known as Gold Beach, was the code name for one of the five areas of the Allied invasion of German-occupied France in the Normandy landings on 6 June 1944, during the Second World War. Gold, the central of the five areas, was located between Port-en-Bessin on the west and La Riviere on the east. High cliffs at the western end of the zone meant that the landings took place on the flat section between Le Hamel and La Riviere, in the sectors code-named Jig and King. Taking Gold was to be the responsibility of the British Army, with sea transport, mine sweeping, and a naval bombardment force provided by the Royal Navy as well as elements from the Dutch, Polish and other Allied navies. - Mulberry harbours were temporary portable harbours developed by the British during World War II to facilitate the rapid offloading of cargo onto beaches during the Allied invasion of Normandy in June 1944. After the Allies successfully held beachheads following D-Day, two prefabricated harbours were taken in sections across the English Channel from Britain with the invading army and assembled off Omaha (Mulberry "A") and Gold Beach (Mulberry "B"). - Robert Lochner MBE ( 1904 -- 1965 ) was the inventor of The Bombardon Breakwater , an integral part of the Mulberry Harbour , which helped the successful invasion of the Normandy Beaches in June 1944 . What object entity has the relation of 'military branch' with the subject 'robert lochner '? Choices: - army - british army - royal navy
A:
royal navy