Generate a topic word for the given sentence. A topic word is usually the name of a person, place, animal, concept or object the sentence is focusing on.

[Q]: diana ross is a famous american soul and pop singer.
[A]: diana ross


[Q]: hadstock is a village and civil parish in uttlesford, essex, england.
[A]: hadstock


[Q]: tropical storm allison was one of the worst tropical storms in the history of the united states.
[A]:
tropical storm allison