Final answer:
The U.S. Navy vehicle that sank in the Atlantic Ocean in 1936, causing the loss of 73 lives, was a Zeppelin. This incident foreshadowed the Hindenburg disaster, which also involved a hydrogen-filled zeppelin.
Step-by-step explanation:
In 1936, four years before the Hindenburg disaster, a U.S. Navy airship plunged into the Atlantic Ocean, killing 73 people. The correct answer to your question is c) Zeppelin. The Hindenburg itself was also a zeppelin, which was a type of airship that used hydrogen for buoyancy. The tragic events surrounding airships highlight the dangers inherent in using hydrogen, which, as demonstrated in the Hindenburg disaster, ignites easily when exposed to oxygen, leading to catastrophic outcomes. Modern airships now use helium, a non-flammable alternative, to ensure safety.