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.
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Question: plumbaginaceae is a family of flowering plants are about 560 species in 10 genera found all over the world.

Answer: plumbaginaceae


Question: gossliwil is a former municipality in the district bucheggberg, in the canton of solothurn, switzerland.

Answer: gossliwil


Question: nada surf is an american alternative rock band from new york.

Answer:
nada surf